Hearing Loss: Noise-Induced https://greenmedinfo.com/taxonomy/term/5073/all en . The antioxidants N Acetyl-L-Cysteine and vitamins A, C, E with the vasodilator magnesium presumably counteract the free radical induced damage associated with noise-induced hearing loss. https://greenmedinfo.com/article/antioxidants-n-acetyl-l-cysteine-and-vitamins-c-e-vasodilator-magnesium-presum PMID:  PLoS One. 2009;4(6):e5987. Epub 2009 Jun 24. PMID: 20809938 Abstract Title:  Uniform comparison of several drugs which provide protection from noise induced hearing loss. Abstract:  ABSTRACT: BACKGROUND: The ability of drugs to reduce noise induced hearing loss (NIHL) has been evaluated in diverse experimental conditions (animal species, noise intensities, durations, assessment techniques, etc), making it difficult to assess their relative efficacy. The present study was designed to provide more uniform comparisons and to allow to a better understanding of the mechanism of the NIHL. Methods: The drugs studied included furosemide (loop diuretic) and the antioxidants N Acetyl-L-Cysteine, vitamins A, C, E with the vasodilator magnesium. Mice were exposed to a continuous broadband noise (113 dB SPL for 3.5 hours) and the NIHL was assessed in all animals before noise exposure and 1 week after with auditory nerve brainstem evoked responses (ABR) to broadband clicks and to 8 kHz tone bursts. RESULTS: Each of the drugs alone and in combination led to similar reductions in NIHL. CONCLUSIONS: The loop diuretic furosemide, by reducing the magnitude of the endocochlear potential in scala media, probably depressed active vibrations of the outer hair cells and basilar membrane, resulting in reduction of free radical formation during the noise exposure. The antioxidants N Acetyl-L-Cysteine and vitamins A, C, E with the vasodilator magnesium presumably counteract the free radicals. Thus, the administration of the antioxidants to animals in which free radical formation had already been reduced by previous injection of furosemide did not have an additional protective effect on the NIHL. https://greenmedinfo.com/article/antioxidants-n-acetyl-l-cysteine-and-vitamins-c-e-vasodilator-magnesium-presum#comments Hearing Loss Hearing Loss: Noise-Induced Magnesium Vitamin A Vitamin C Vitamin E Animal Study Thu, 14 Oct 2010 20:58:03 +0000 greenmedinfo 57732 at https://greenmedinfo.com Animals treated with magnesium after acoustic trauma have significant reduction in hair cell loss in the basal region. https://greenmedinfo.com/article/animals-treated-magnesium-after-acoustic-trauma-have-significant-reduction-hai PMID:  Acta Otolaryngol. 2006 Feb;126(2):122-9. PMID: 16428187 Abstract Title:  Therapeutic efficacy of magnesium after acoustic trauma caused by gunshot noise in guinea pigs. Abstract:  CONCLUSIONS: The present findings show that magnesium administration can significantly reduce threshold shift 7 days after gunshot noise exposure. However, this improvement seems to be temporary, suggesting a probable advantage in prolonging the treatment. OBJECTIVE: To evaluate the therapeutic efficacy of magnesium administration after hearing loss induced by gunshot noise. MATERIAL AND METHODS: Forty-eight guinea pigs were exposed to an impulse noise (blank shot from a rifle; 170 or 176 dB SPL peak). The therapeutic efficacy of magnesium was evaluated by administering either the treatment or a placebo to the traumatized animals for 7 days, beginning 1 h after the trauma. Auditory function was explored for up to 14 days of recovery by recording the compound action potential in the round window. The functional study of hearing was supplemented by histological analysis. RESULTS: The threshold shifts of the 170-dB SPL group that received magnesium were significantly lower than those of controls after 2 and 7 days of recovery, but no significant difference was evidenced at 14 days in this group, nor at any time in the 176-dB SPL group. Animals treated with magnesium after the 176-dB SPL exposure had a significant reduction in hair cell loss in the basal region. https://greenmedinfo.com/article/animals-treated-magnesium-after-acoustic-trauma-have-significant-reduction-hai#comments Hearing Loss Hearing Loss: Noise-Induced Magnesium Animal Study Thu, 14 Oct 2010 21:01:24 +0000 greenmedinfo 57735 at https://greenmedinfo.com Baicalein, a compound found within Chinese skullcap, prevents noise-induced hearing loss. https://greenmedinfo.com/article/baicalein-compound-found-within-chinese-skullcap-prevents-noise-induced-hearin PMID:  Neurosci Lett. 2010 Jan 29;469(3):298-302. Epub 2009 Dec 11. PMID: 20004700 Abstract Title:  Effect of baicalein from Scutellaria baicalensis on prevention of noise-induced hearing loss. Abstract:  Noise-induced hearing loss (NIHL) has been thought to primarily involve damage to the sensory hair cells of the cochlea via mechanical and metabolic mechanisms. This study examined the effects of baicalin, baicalein, and Scutellaria baicalensis (SB) extract against NIHL in a mouse model. Mice received oral treatment with SB, baicalin, baicalein beginning 30 min prior to noise exposure and continuing once daily throughout the study. Hearing threshold shift was assessed by auditory brain stem responses for 35 days following noise exposure. Central auditory function was evaluated by auditory middle latency responses. Cochlear function was determined based on transient evoked otoacoustic emissions. SB significantly reduced threshold shift, central auditory function damage, and cochlear function deficits, suggesting that SB may protect auditory function in NIHL and that the active constituent may be a flavonoid, baicalein. https://greenmedinfo.com/article/baicalein-compound-found-within-chinese-skullcap-prevents-noise-induced-hearin#comments Hearing Loss: Noise-Induced Skullcap: Chinese Animal Study Sat, 06 Mar 2010 14:47:39 +0000 greenmedinfo 53360 at https://greenmedinfo.com Coenzyme Q10 prevents noise-induced hearing loss in a guinea pig model. https://greenmedinfo.com/article/coenzyme-q10-prevents-noise-induced-hearing-loss-guinea-pig-model PMID:  Brain Res. 2009 Feb 27;1257:108-16. Epub 2008 Dec 24. PMID: 19133240 Abstract Title:  Water-soluble Coenzyme Q10 formulation (Q-ter) promotes outer hair cell survival in a guinea pig model of noise induced hearing loss (NIHL). Abstract:  The mitochondrial respiratory chain is a powerful source of reactive oxygen species (ROS) also in noise induced hearing loss (NIHL) and anti-oxidants and free-radicals scavengers have been shown to attenuate the damage. Coenzyme Q(10) (CoQ(10)) or ubiquinone has a bioenergetic role as a component of the mithocondrial respiratory chain, it inhibits mitochondrial lipid peroxidation, inducing ATP production and it is involved in ROS removal and prevention of oxidative stress-induced apoptosis. However the therapeutic application of CoQ(10) is limited by the lack of solubility and poor bio- availability, therefore it is a challenge to improve its water solubility in order to ameliorate the efficacy in tissues and fluids. This study was conducted in a model of acoustic trauma in the guinea pig where the effectiveness of CoQ(10) was compared with a soluble formulation of CoQ(10) (multicomposite CoQ(10) Terclatrate, Q-ter) given intraperitoneally 1 h before and once daily for 3 days after pure tone noise exposure (6 kHz for 1 h at 120 dB SPL). Functional and morphological studies were carried out by measuring auditory brainstem responses, scanning electron microscopy for hair cell loss count, active caspase 3 staining and terminal deoxynucleotidyl transferase-mediated dUTP labelling assay in order to identify initial signs of apoptosis. Treatments decreased active caspase 3 expression and the number of apoptotic cells, but animals injected with Q-ter showed a greater degree of activity in preventing apoptosis and thus in improving hearing. These data confirm that solubility of Coenzyme Q(10) improves the ability of CoQ(10) in preventing oxidative injuries that result from mitochondrial dysfunction. https://greenmedinfo.com/article/coenzyme-q10-prevents-noise-induced-hearing-loss-guinea-pig-model#comments Coenzyme Q10 Hearing Loss: Noise-Induced Apoptotic Animal Study Fri, 11 Jun 2010 22:18:23 +0000 greenmedinfo 55369 at https://greenmedinfo.com Creatine may attenuate noise-induced hearing loss in animals. https://greenmedinfo.com/article/creatine-may-attenuate-noise-induced-hearing-loss-animals PMID:  Brain Res. 2007 May 7;1148:83-9. Epub 2007 Feb 21. PMID: 17359945 Abstract Title:  Creatine and tempol attenuate noise-induced hearing loss. Abstract:  To define the role of free radical formation and potential energy depletion in noise induced hearing loss (NIHL), we measured the effectiveness of tempol (free radical scavenger) and creatine (enhances cellular energy storage) alone and in combination to attenuate NIHL. Guinea pigs were divided into four treatment groups: controls, 3% creatine diet (2 weeks prior to noise exposure), tempol (3 mM in drinking water 2 weeks prior to exposure), and creatine plus tempol and exposed to 120 dB SPL one-octave band noise centered at 4 kHz for 5 h. The noise-only control group showed frequency-dependent auditory threshold shifts (measured by auditory brainstem response, ABR) of up to 73 dB (16 kHz) on day 1, and up to 50 dB (8 kHz) on day 10. Creatine-treated subjects had significantly smaller ABR threshold shifts on day 1 and on day 10. Tempol alone significantly reduced ABR threshold shifts on day 10 but not on day 1. ABR shifts after combination treatment were similar to those in the creatine group. Hair cell loss on day 10 was equally attenuated by creatine and tempol alone or in combination. Our results indicate that the maintenance of ATP levels is important in attenuating both temporary and permanent NIHL, while the scavenging of free radicals provides protection from permanent NIHL. https://greenmedinfo.com/article/creatine-may-attenuate-noise-induced-hearing-loss-animals#comments Creatine Hearing Loss Hearing Loss: Noise-Induced Oxidative Stress Antioxidants Drug-Plant-Vitamin Synergies Animal Study Thu, 14 Oct 2010 20:59:07 +0000 greenmedinfo 57733 at https://greenmedinfo.com Effect of phlorofucofuroeckol A and dieckol extracted from Ecklonia cava on noise-induced hearing loss in a mouse model. https://greenmedinfo.com/article/effect-phlorofucofuroeckol-and-dieckol-extracted-ecklonia-cava-noise-induced-h PMID:  Mar Drugs. 2021 Aug 1 ;19(8). Epub 2021 Aug 1. PMID: 34436282 Abstract Title:  Effect of Phlorofucofuroeckol A and Dieckol Extracted fromon Noise-induced Hearing Loss in a Mouse Model. Abstract:  One of the well-known causes of hearing loss is noise. Approximately 31.1% of Americans between the ages of 20 and 69 years (61.1 million people) have high-frequency hearing loss associated with noise exposure. In addition, recurrent noise exposure can accelerate age-related hearing loss. Phlorofucofuroeckol A (PFF-A) and dieckol, polyphenols extracted from the brown alga, are potent antioxidant agents. In this study, we investigated the effect of PFF-A and dieckol on the consequences of noise exposure in mice. In 1,1-diphenyl-2-picrylhydrazyl assay, dieckol and PFF-A both showed significant radical-scavenging activity. The mice were exposed to 115 dB SPL of noise one single time for 2 h. Auditory brainstem response(ABR) threshold shifts 4 h after 4 kHz noise exposure in mice that received dieckol were significantly lower than those in the saline with noise group. The high-PFF-A group showed a lower threshold shift at click and 16 kHz 1 day after noise exposure than the control group. The high-PFF-A group also showed higher hair cell survival than in the control at 3 days after exposure in the apical turn. These results suggest that noise-induced hair cell damage in cochlear and the ABR threshold shift can be alleviated by dieckol and PFF-A in the mouse. Derivatives of these compounds may be applied to individuals who are inevitably exposed to noise, contributing to the prevention of noise-induced hearing loss with a low probability of adverse effects. <p><a href="https://greenmedinfo.com/article/effect-phlorofucofuroeckol-and-dieckol-extracted-ecklonia-cava-noise-induced-h" target="_blank">read more</a></p> https://greenmedinfo.com/article/effect-phlorofucofuroeckol-and-dieckol-extracted-ecklonia-cava-noise-induced-h#comments Hearing Loss: Noise-Induced Phlorotannins Animal Study Sun, 17 Oct 2021 18:45:11 +0000 greenmedinfo 247402 at https://greenmedinfo.com Ginkgo biloba extract was beneficial for the treatment of existing noise induced hearing loss and tinnitus. https://greenmedinfo.com/article/ginkgo-biloba-extract-was-beneficial-treatment-existing-noise-induced-hearing- PMID:  PLoS One. 2016 ;11(6):e0157574. Epub 2016 Jun 17. PMID: 27315063 Abstract Title:  Therapeutic Value of Ginkgo biloba Extract EGb 761® in an Animal Model (Meriones unguiculatus) for Noise Trauma Induced Hearing Loss and Tinnitus. Abstract:  Noise induced hearing loss (NIHL) is a common disease in modern societies and may lead to maladaptations within the auditory system that finally result in subjective tinnitus. Available therapies may only alleviate the symptoms rather than restore normal hearing. In a previous study we demonstrated that the prophylactic application of Ginkgo biloba extract EGb 761® significantly reduces NIHL and tinnitus development in our Mongolian gerbil (Meriones unguiculatus) animal model. Here, we tested whether the application of EGb 761® has beneficial effects after the formation of permanent NIHL and tinnitus. To this end we monitored the therapeutic effects of EGb761® on noise trauma-induced changes in signal processing within the auditory system of our animal model by behavioral (acoustic startle response, ASR) and electrophysiological approaches (auditory brainstem responses, ABR). We found that-in contrast to vehicle-three weeks of daily oral EGb 761®treatment (100 mg/kg body weight) led to a restoration of hearing thresholds back to pre-trauma conditions. In addition, all 9 animals that displayed behavioral signs of subjective tinnitus showed improvement, with 7 of them showing complete relief of tinnitus symptoms during the time of EGb 761® treatment. After discontinuation of EGb 761® treatment, tinnitus related behavior reappeared in all but one of these animals while auditory thresholds remained restored. A detailed analysis of ABR waves revealed that EGb 761® treatment did not simply change auditory processing back to pre-trauma conditions, but led to subtle changes of ABR wave amplitude and latency at different levels of the auditory pathway, with an overall increase of response to low stimulus intensities and a decrease at high intensities. The functional relevance of these changes may be the observed improvement of hearingthresholds while at the same time suppression of responses to high stimulus intensities may point to a global inhibitory mechanism that counteracts tinnitus. https://greenmedinfo.com/article/ginkgo-biloba-extract-was-beneficial-treatment-existing-noise-induced-hearing-#comments Ginkgo biloba Hearing Loss: Noise-Induced Tinnitus Plant Extracts Animal Study Fri, 24 Jun 2016 08:43:32 +0000 greenmedinfo 129147 at https://greenmedinfo.com Ginsenoside Rd ameliorates auditory cortex injury associated with military aviation noise-induced hearing loss. https://greenmedinfo.com/article/ginsenoside-rd-ameliorates-auditory-cortex-injury-associated-military-aviation PMID:  Front Physiol. 2020 ;11:788. Epub 2020 Jul 21. PMID: 32792971 Abstract Title:  Ginsenoside Rd Ameliorates Auditory Cortex Injury Associated With Military Aviation Noise-Induced Hearing Loss by Activating SIRT1/PGC-1α Signaling Pathway. Abstract:  Free radicals and oxidative stress play an important role in the pathogenesis of noise-induced hearing loss (NIHL). Some ginseng monomers showed certain therapeutic effects in NIHL by scavenging free radicals. Therefore, we hypothesized that ginsenoside Rd (GSRd) may exert neuroprotective effects after noise-induced auditory system damage through a mechanism involving the SIRT1/PGC-1α signaling pathway. Forty-eight guinea pigs were randomly divided into four equal groups (normal control group, noise group, experimental group that received GSRd dissolved in glycerin through an intraperitoneal injection at a dose of 30 mg/kg body weight from 5 days before noise exposure until the end of the noise exposure period, and experimental control group). Hearing levels were examined by auditory brainstem response (ABR) and distortion product otoacoustic emission (DPOAE). Hematoxylin-eosin and Nissl staining were used to examine neuron morphology. RT-qPCR and western blotting analysis were used to examine SIRT1/PGC-1α signaling and apoptosis-related genes, including Bax and Bcl-2, in the auditory cortex. Bax and Bcl-2 expression was assessed via immunohistochemistry analysis. Superoxide dismutase (SOD), malondialdehyde (MDA), and glutathione peroxidase (GSH-Px) levels were determined using a commercial testing kit. Noise exposure was found to up-regulate ABR threshold and down-regulate DPOAE amplitudes, with prominent morphologic changes and apoptosis of the auditory cortex neurons (<p><a href="https://greenmedinfo.com/article/ginsenoside-rd-ameliorates-auditory-cortex-injury-associated-military-aviation" target="_blank">read more</a></p> https://greenmedinfo.com/article/ginsenoside-rd-ameliorates-auditory-cortex-injury-associated-military-aviation#comments Ginsenosides Hearing Loss: Noise-Induced Anti-Apoptotic SIRT1 Activator In Vitro Study Sat, 05 Sep 2020 18:18:44 +0000 greenmedinfo 226392 at https://greenmedinfo.com Hydrogen in drinking water attenuates noise-induced hearing loss in guinea pigs. https://greenmedinfo.com/article/hydrogen-drinking-water-attenuates-noise-induced-hearing-loss-guinea-pigs PMID:  Neurosci Lett. 2011 Jan 3 ;487(1):12-6. Epub 2010 Oct 1. PMID: 20888392 Abstract Title:  Hydrogen in drinking water attenuates noise-induced hearing loss in guinea pigs. Abstract:  It has been shown that molecular hydrogen acts as a therapeutic and preventive antioxidant by selectively reducing the hydroxyl radical, the most cytotoxic of the reactive oxygen species. In the present study, we tested the hypothesis that acoustic damage in guinea pigs can be attenuated by the consumption of molecular hydrogen. Guinea pigs received normal water or hydrogen-rich water for 14 days before they were exposed to 115 dB SPL 4-kHz octave band noise for 3h. Animals in each group underwent measurements for auditory brainstem response (ABR) or distortion-product otoacoustic emissions (DPOAEs) before the treatment (baseline) and immediately, 1, 3, 7, and 14 days after noise exposure. The ABR thresholds at 2 and 4 kHz were significantly better on post-noise days 1, 3, and 14 in hydrogen-treated animals when compared to the normal water-treated controls. Compared to the controls, the hydrogen-treated animals showed greater amplitude of DPOAE input/output growth functions during the recovery process, with statistical significance detected on post-noise days 3 and 7. These findings suggest that hydrogen can facilitate the recovery of hair cell function and attenuate noise-induced temporary hearing loss. <p><a href="https://greenmedinfo.com/article/hydrogen-drinking-water-attenuates-noise-induced-hearing-loss-guinea-pigs" target="_blank">read more</a></p> https://greenmedinfo.com/article/hydrogen-drinking-water-attenuates-noise-induced-hearing-loss-guinea-pigs#comments Hearing Loss: Noise-Induced Hydrogen Water Animal Study Thu, 11 Oct 2018 01:29:43 +0000 greenmedinfo 172173 at https://greenmedinfo.com Magnesium has a therapeutic effect on noise-induced hearing loss. https://greenmedinfo.com/article/magnesium-has-therapeutic-effect-noise-induced-hearing-loss PMID:  Noise Health. 2001;3(11):79-84. PMID: 12689450 Abstract Title:  Therapeutic effect of magnesium on noise-induced hearing loss. Abstract:  This study examined the therapeutic effect of magnesium (Mg) on noise trauma in anesthetized guinea pigs exposed to an impulse noise series (1/s) of Lpeak 167 dB (Leq,1s 127 dB) for 38 min. The permanent hearing threshold shift (PTS) was measured 1 week post-exposure, using auditory brain stem response audiometry (frequency range, 0.5-32 kHz). The total Mg concentrations of perilymph, cerebrospinal fluid and plasma were analyzed by atomic absorption spectrometry. In a first series, animals maintained on physiologically low Mg received subcutaneous injections of either different Mg doses (0.11-0.33 mmol MgSO4/100 g per day) for 3 days and drinking water with an additive of 39 mmol MgCl2/l for 1 week or saline as a placebo and tap water alone. The treatment began immediately after the impulse noise exposure. The dose of 0.29 mmol Mg/100 g per day was found to be most effective and reduced the hearing loss by 13-20 dB compared to placebo. The PTS and the perilymph Mg level showed a close negative correlation, suggesting that the intracochlear Mg level plays an important role in bringing about these protective effects. In a second series, we tested the therapeutic efficacy as a function of the post-exposure time of onset of the optimal Mg treatment (1 min, 2 and 4 hours), using normal Mg animals. The therapeutic effect decreased with the length of time elapsed between the end of exposure and the beginning of treatment. In a parallel scanning electron microscopic test, we also found a Mg-related difference in the susceptibility of hair cell stereocilia to impulse noise exposure. https://greenmedinfo.com/article/magnesium-has-therapeutic-effect-noise-induced-hearing-loss#comments Hearing Loss Hearing Loss: Noise-Induced Magnesium Animal Study Thu, 14 Oct 2010 21:04:39 +0000 greenmedinfo 57738 at https://greenmedinfo.com Magnesium may attenuate trauma-induced hearing loss in guinea pigs. https://greenmedinfo.com/article/magnesium-may-attenuate-trauma-induced-hearing-loss-guinea-pigs PMID:  Exp Biol Med (Maywood). 2007 May;232(5):674-81. PMID: 19084059 Abstract Title:  Long-term administration of magnesium after acoustic trauma caused by gunshot noise in guinea pigs. Abstract:  In a previous study we observed that a 7-day post-trauma magnesium treatment significantly reduced auditory threshold shifts measured 7 days after gunshot noise exposure. However this improvement was only temporary, suggesting that it could be potentially beneficial to prolong this treatment. The aim of the present study was to evaluate the efficacy of a long-term (1 month) magnesium treatment after an impulse noise trauma, in comparison with either a 7-day magnesium treatment, an administration of methylprednisolone (conventional treatment), or a placebo (NaCl). Guinea pigs were exposed to impulse noise (three blank gunshots, 170 dB SPL peak). They received one of the four treatments, 1 h after the noise exposure. Auditory function was explored by recording the auditory brainstem response (ABR) and measuring the distortion product otoacoustic emissions (DPOAE) over a 3-month recovery period after the gunshot exposure. The functional hearing study was supplemented by a histological analysis. The results showed that a 1-month treatment with magnesium was the most effective treatment in terms of hair cell preservation. The DPOAE confirmed this effectiveness. Methylprednisolone accelerated recovery but its final efficacy remained moderate. It is probable that magnesium acts on the later metabolic processes that occur after noise exposure. Multiple mechanisms could be involved: calcium antagonism, anti-ischaemic effect or NMDA channel blockage. Regardless of the specific mechanism, a 1-month treatment with magnesium clearly attenuates NIHL, and presents the advantage of being safe for use in humans. https://greenmedinfo.com/article/magnesium-may-attenuate-trauma-induced-hearing-loss-guinea-pigs#comments Hearing Loss Hearing Loss: Noise-Induced Magnesium Neuroprotective Agents Animal Study Thu, 14 Oct 2010 21:00:34 +0000 greenmedinfo 57734 at https://greenmedinfo.com Magnesium prevents noise-induced hearing loss and/or trauma in guinea-pigs. https://greenmedinfo.com/article/magnesium-prevents-noise-induced-hearing-loss-andor-trauma-guinea-pigs PMID:  J Basic Clin Physiol Pharmacol. 2003;14(2):119-36. PMID: 14558727 Abstract Title:  Preventing noise induced otoacoustic emission loss by increasing magnesium (Mg2+) intake in guinea-pigs. Abstract:  This study aimed to explore the effects of increased Mg2+ intake on the activity of the outer hair cells as manifested in Click and Distortion Evoked Otoacoustic Emissions (CEOAEs; DPOAEs) in 25 animals. Thirteen animals were fed with high Mg2+ intake (39 mmol Mg2+/l in drinking water) and 12 without the Mg2+ additive. The OAE amplitudes and frequency ranges as well as the DPOAE thresholds were affected significantly less by noise exposure in the animals fed Mg2+-enriched water. Following the exposure, the auditory recovery was faster in the high than the low Mg2+ animals (controls). In addition, a relationship was found between the Mg2+ level and the emission loss. The post-exposure measures may result from the effect of Mg2+ on cochlear metabolic processes and vascular microcirculation. The results demonstrate that pre-existing low Mg2+ levels will exacerbate noise induced hearing loss (NIHL), and increased Mg2+ intake provides a significant biological cochlear protective effect. https://greenmedinfo.com/article/magnesium-prevents-noise-induced-hearing-loss-andor-trauma-guinea-pigs#comments Hearing Loss Hearing Loss: Noise-Induced Magnesium Animal Study Thu, 14 Oct 2010 21:02:33 +0000 greenmedinfo 57736 at https://greenmedinfo.com N-Acetyl-cysteine has a protective effect against noise-induced temporary threshold shift in male workers. https://greenmedinfo.com/article/n-acetyl-cysteine-has-protective-effect-against-noise-induced-temporary-thresh PMID:  Hear Res. 2010 Jul 16. Epub 2010 Jul 16. PMID: 20638463 Abstract Title:  N-Acetyl-cysteine against noise-induced temporary threshold shift in male workers. Abstract:  Previous animal studies showed protective effects of antioxidant medicines against noise-induced hearing loss (NIHL). It is unclear whether antioxidants would protect humans from NIHL. We conducted a study to determine whether N-Acetyl-cysteine (NAC) protected men against noise-induced temporary threshold shift (TTS), and whether subgroups with genetic polymorphisms of glutathione S-transferase (GST) T1 and M1 responded to NAC differently. In this prospective, double-blind, crossover study, 53 male workers were randomly assigned to receive either NAC (1200 mg/day, 14 days) during the first period and placebo during the second period, or placebo during the first period and NAC during the second period. Dosing periods were separated by a washout period of 2 weeks. The hearing threshold changes were determined before and after each dosing period. Pre-shift hearing threshold for high frequencies was 19.1 dB. Daily exposure to noise ranged from 88.4 to 89.4 dB. The noise levels of different frequencies ranged from 80.0 to 89.4 dB with a peak-value at 4 kHz. NAC significantly reduced TTS (p = 0.03). When the participants were grouped by GST M1/T1 genotypes, the NAC effect was only significant among workers with null genotypes in both GSTM1 and GSTT1 (p = 0.004). NAC may prevent noise-induced TTS among occupationally noise-exposed men. The protective effect of NAC was more prominent in subjects with both GSTM1-null and GSTT1-null genotypes. (clinicaltrials.gov Identifier: NCT00552786). https://greenmedinfo.com/article/n-acetyl-cysteine-has-protective-effect-against-noise-induced-temporary-thresh#comments Hearing Loss: Noise-Induced NAC (N-acetyl-L-cysteine) Human Study Mon, 16 Aug 2010 18:34:44 +0000 greenmedinfo 55947 at https://greenmedinfo.com Nicotinamide adenine dinucleotide protects from noise induced hearing loss in this animal study. https://greenmedinfo.com/article/nicotinamide-adenine-dinucleotide-protects-noise-induced-hearing-loss-animal-s PMID:  Cell Metab. 2014 Dec 2 ;20(6):1059-68. PMID: 25470550 Abstract Title:  Activation of SIRT3 by the NAD(+) Precursor Nicotinamide Riboside Protects from Noise-Induced Hearing Loss. Abstract:  Intense noise exposure causes hearing loss by inducing degeneration of spiral ganglia neurites that innervate cochlear hair cells. Nicotinamide adenine dinucleotide (NAD(+)) exhibits axon-protective effects in cultured neurons; however, its ability to block degeneration in vivo has been difficult to establish due to its poor cell permeability and serum instability. Here, we describe a strategy to increase cochlear NAD(+) levels in mice by administering nicotinamide riboside (NR), a recently described NAD(+) precursor. We find that administration of NR, even after noise exposure, prevents noise-induced hearing loss (NIHL) and spiral ganglia neurite degeneration. These effects are mediated by the NAD(+)-dependent mitochondrial sirtuin, SIRT3, since SIRT3-overexpressing mice are resistant to NIHL and SIRT3 deletion abrogates the protective effects of NR and expression of NAD(+) biosynthetic enzymes. These findings reveal that administration of NR activates a NAD(+)-SIRT3 pathway that reduces neurite degeneration caused by noise exposure. https://greenmedinfo.com/article/nicotinamide-adenine-dinucleotide-protects-noise-induced-hearing-loss-animal-s#comments Hearing Loss: Noise-Induced Nicotinamide adenine dinucleotide (NADH) Animal Study Mon, 08 Dec 2014 13:26:13 +0000 greenmedinfo 115417 at https://greenmedinfo.com Preventive effects of ginkgo-extract EGb 761® on noise trauma-induced cochlear synaptopathy. https://greenmedinfo.com/article/preventive-effects-ginkgo-extract-egb-761-noise-trauma-induced-cochlear-synapt PMID:  Nutrients. 2022 Jul 22 ;14(15). Epub 2022 Jul 22. PMID: 35893868 Abstract Title:  Preventive Effects of Ginkgo-Extract EGb 761on Noise Trauma-Induced Cochlear Synaptopathy. Abstract:  Noise trauma-induced loss of ribbon synapses at the inner hair cells (IHC) of the cochlea may lead to hearing loss (HL), resulting in tinnitus. We are convinced that a successful and sustainable therapy of tinnitus has to treat both symptom and cause. One of these causes may be the mentioned loss of ribbon synapses at the IHC of the cochlea. In this study, we investigated the possible preventive and curative effects of theextract EGb 761on noise-induced synaptopathy, HL, and tinnitus development in Mongolian gerbils (). To this end, 37 male animals received EGb 761or placebo orally 3 weeks before (16 animals) or after (21 animals) a monaural acoustic noise trauma (2 kHz, 115 dB SPL, 75 min). Animals&#039; hearing thresholds were determined by auditory brainstem response (ABR) audiometry. A possible tinnitus percept was assessed by the gap prepulse inhibition acoustic startle reflex (GPIAS) response paradigm. Synaptopathy was quantified by cochlear immunofluorescence histology, counting the ribbon synapses of 15 IHCs at 11 different cochlear frequency locations per ear. We found a clear preventive effect of EGb 761on ribbon synapse numbers with the surprising result of a significant increase in synaptic innervation on the trauma side relative to placebo-treated animals. Consequently, animals treated with EGb 761before noise trauma did not develop a significant HL and were also less affected by tinnitus compared to placebo-treated animals. On the other hand, we did not see a curative effect (EGb 761treatment after noise trauma) of the extract on ribbon synapse numbers and, consequently, a significant HL and no difference in tinnitus development compared to the placebo-treated animals. Taken together, EGb 761prevented noise-induced HL and tinnitus by protecting from noise trauma-induced cochlear ribbon synapse loss; however, in our model, it did not restore lost ribbon synapses. <p><a href="https://greenmedinfo.com/article/preventive-effects-ginkgo-extract-egb-761-noise-trauma-induced-cochlear-synapt" target="_blank">read more</a></p> https://greenmedinfo.com/article/preventive-effects-ginkgo-extract-egb-761-noise-trauma-induced-cochlear-synapt#comments Ginkgo biloba Hearing Loss: Noise-Induced Prophylactic Agents Plant Extracts Animal Study Sat, 24 Dec 2022 20:07:57 +0000 greenmedinfo 268304 at https://greenmedinfo.com