Chronic ethanol ingestion induces oxidative kidney injury through taurine-inhibitable inflammation

Effects of short- and long-term use of propolis extracts on liver and kidney in rats

Propolis is widely used as a supplementary food product for its health benefits. The aim of this study was to determine the effects of commercial propolis extracts on the liver and kidney. Propolis extracts (250 mg/kgbw/day) were administered orally to adult male Wistar albino rats in solvents of ethanol, propylene glycol, water, and olive oil. Liver enzyme levels were determined biochemically in blood samples, and histopathological examinations were performed on the liver. Damage rate in both kidney tissue in the propolis-ethanol extract group increased significantly compared with the other groups after 30 and 90 days of application (p < .05). According to the results, ethanol, used as a common solvent in propolis products, may adversely affect the liver in long-term use. The data indicate that propolis-olive oil extract may be an essential alternative due to its effective and reliable properties.

Effects of hesperidin on the histological structure, oxidative stress, and apoptosis in the liver and kidney induced by NiCl2

The aim of this study was to investigate the effect of hesperidin on the liver and kidney dysfunctions induced by nickel. The mice were divided into six groups: nickel treatment with 80 mg/kg, 160 mg/kg, 320 mg/kg hesperidin groups, 0.5% CMC-Na group, nickel group, and blank control group. Histopathological techniques, biochemistry, immunohistochemistry, and the TUNEL method were used to study the changes in structure, functions, oxidative injuries, and apoptosis of the liver and kidney. The results showed that hesperidin could alleviate the weight loss and histological injuries of the liver and kidney induced by nickel, and increase the levels of lactate dehydrogenase (LDH), alanine aminotransferase (GPT), glutamic oxaloacetic transaminase (GOT) in liver and blood urea nitrogen (BUN), creatinine (Cr) and N-acetylglucosidase (NAG) in kidney. In addition, hesperidin could increase the activities of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and glutathione peroxidase (GSH-Px) in the liver and kidney, decrease the content of malondialdehyde (MDA) and inhibit cell apoptosis. It is suggested that hesperidin could help inhibit the toxic effect of nickel on the liver and kidney.

Oxidized phospholipid-protein adducts: The future targets of interest

Phospholipids are key biomolecules with important roles as components of membranes, lipoproteins and as signalling molecules. However, phospholipids are quite prone to oxidation. Upon oxidation they generate several types of oxidation products including long chain oxidation products, as hydroperoxyl and hydroxy derivatives, and highly reactive oxidation products, like small aldehydes and truncated oxidized phospholipids. The formation of protein adducts with small electrophilic aldehydes (like malondialdehyde) is now well studied, however, the aggregation of proteins with truncated oxidized phospholipids lacks research. This paper provides a short overview of the formation of protein adducts with truncated oxidized phospholipids as well as a gathering of the research on this topic. The literature found reports the synthesis, detection and fragmentation of this type of adducts, mainly focusing on truncated oxidized phospholipid' products from phosphatidylcholine class and few peptides and proteins, as human serum albumin and Apo B100, leaving unattended the screening in vivo and in disease correlation, thus lacking possible association with their biological role. These adducts are a consequence of oxidative modifications to important biomolecules and their involvement in the organism is still unclear, revealing the urgent need for more investigation in this area.

Alcohol-Attributable Death and Burden of Illness among Aboriginal and Non-Aboriginal Populations in Remote Australia, 2014-2018

Harmful use of alcohol is a problem in the Northern Territory (NT), Australia. The aim of this study was to assess and compare alcohol-attributable deaths and the contribution of alcohol to the burden of disease and injury (BOD) among the Aboriginal and non-Aboriginal populations in the NT between 2014 and 2018. The alcohol-use data for adults aged 15+ years old in the NT population was taken from the 2016 National Drug Strategy Household Survey. BOD was measured in disability-adjusted life years (DALY) as part of the NT BOD study. Population-attributable fractions were derived to analyse deaths and BOD. Between 2014 and 2018, 673 Aboriginal and 392 non-Aboriginal people died of harmful use of alcohol, accounting for 26.3% and 12.9% of the total deaths in the Aboriginal and non-Aboriginal population, respectively. Alcohol caused 38,596 and 15,433 DALY (19.9% and 10.2% of the total), respectively, in the NT Aboriginal and non-Aboriginal population for the same period. The alcohol-attributable DALY rate in the Aboriginal population was 10,444.6 per 100,000 persons, six times the non-Aboriginal rate. This study highlights the urgent need to reduce harmful alcohol use in the NT, which disproportionately affects Aboriginal peoples in rural and remote areas.

Yak milk protects against alcohol-induced liver injury in rats

The protective effects of yak milk (YM) against chronic alcoholic liver injury in rats were investigated in this study. Histologic and biochemical analyses demonstrated that YM consumption ameliorates alcohol-induced liver injury by increasing the liver antioxidant enzyme activity and reducing inflammation. Furthermore, microbiome and metabolomic analyses exploring YM's impact on gut microbiota and metabolism found that YM administration regulates gut microbiota composition. Specifically, there was a decrease in the relative abundance of Helicobacter, Streptococcus, Peptococcus and Tyzzerella, along with an increase in Turisibacter and Intestinimonas. Moreover, Pearson analysis indicated positive correlations between Peptococcus and Tyzzerella with ALT and AST levels, while showing a negative correlation with ADH levels. Furthermore, differential metabolite analysis of fecal samples from the YM group identified significant increases in the taurine (2-Aminoethanesulfonic acid), hypotaurine (2-Aminoethanesulfonic Acid) and isethionic acid levels. Finally, KEGG topology analysis highlighted taurine and hypotaurine metabolism as the primary pathways influenced by YM intervention. Therefore, these findings collectively suggest that YM may protect alcohol-exposed rats against liver injury by modulating oxidative stress, inflammatory response, gut microbiota disorder, and metabolic regulation.

Alcohol Intake and Arterial Hypertension: Retelling of a Multifaceted Story

Alcoholic beverages are common components of diets worldwide and understanding their effects on humans' health is crucial. Because hypertension is the leading risk factor for cardiovascular diseases and all-cause mortality, the relationship of alcohol consumption with blood pressure (BP) has been the subject of extensive investigation. For the purpose of this review, we searched the terms "alcohol", "ethanol", and "arterial hypertension" on Pubmed MeSH and selected the most relevant studies. Short-term studies showed a biphasic BP response after ingestion of high doses of alcohol, and sustained alcohol consumption above 30 g/day, significantly, and dose-dependently, increased the risk for hypertension. These untoward effects of alcoholic beverages on BP can be mediated by a multiplicity of neurohormonal mechanisms. In addition to the effects on BP, excess alcohol intake might contribute to cardiac and renal hypertensive organ damage, although some studies suggest possible benefits of moderate alcohol consumption on additional cardiovascular risk factors, such as diabetes and lipoprotein(a). Some intervention studies and cumulative analyses support the evidence of a benefit of the reduction/withdrawal of alcohol consumption on BP and cardiovascular outcomes. This is why guidelines of scientific societies recommend avoidance or limitation of alcohol intake below one unit/day for women and two units/day for men. This narrative article overviews all these topics, providing an update of the current knowledge on the relationship between alcohol and BP.

Association between abnormal plasma metabolism and brain atrophy in alcohol-dependent patients

Objective

In this study, we aimed to characterize the plasma metabolic profiles of brain atrophy and alcohol dependence (s) and to identify the underlying pathogenesis of brain atrophy related to alcohol dependence.

Methods

We acquired the plasma samples of alcohol-dependent patients and performed non-targeted metabolomic profiling analysis to identify alterations of key metabolites in the plasma of BA-ADPs. Machine learning algorithms and bioinformatic analysis were also used to identify predictive biomarkers and investigate their possible roles in brain atrophy related to alcohol dependence.

Results

A total of 26 plasma metabolites were significantly altered in the BA-ADPs group when compared with a group featuring alcohol-dependent patients without brain atrophy (NBA-ADPs). Nine of these differential metabolites were further identified as potential biomarkers for BA-ADPs. Receiver operating characteristic curves demonstrated that these potential biomarkers exhibited good sensitivity and specificity for distinguishing BA-ADPs from NBA-ADPs. Moreover, metabolic pathway analysis suggested that glycerophospholipid metabolism may be highly involved in the pathogenesis of alcohol-induced brain atrophy.

Conclusion

This plasma metabolomic study provides a valuable resource for enhancing our understanding of alcohol-induced brain atrophy and offers potential targets for therapeutic intervention.

Ameliorative Impacts of Wheat Germ Oil against Ethanol-Induced Hepatic and Renal Dysfunction in Rats: Involvement of Anti-Inflammatory, Anti-Apoptotic, and Antioxidant Signaling Pathways

Wheat germ oil (WGO) is a well-known product with anti-inflammatory and antioxidant properties. The current study aimed to investigate the impacts of WGO against ethanol-induced liver and kidney dysfunction at the serum, anti-inflammatory, antioxidants and anti-apoptotic signaling pathways. Rats received saline orally as a negative control or WGO in a dose of 1.5 mL/kg (1400 mg/kg body weight orally) for 15 days. The affected group received ethanol 50% v/v 10 mL/kg (5 g/kg) body weight orally once a day for consecutive 15 days to induce hepatorenal injuries in ethanolic non-treated group. The protective group received WGO daily 1 h before ethanol administration. Serum (1.5 mL) from blood was extracted and examined for the changes in biochemical assessments in serum alkaline phosphatase (ALP), alanine aminotransferase (ALT), bilirubin, serum γ-glutamyl transpeptidase (GGT), total protein, serum albumin, butyrylcholinesterase (BChE), total cholesterol (TC), total triglyceride (TG), urea, creatinine, uric acid, potassium (K⁺), Beta-2 microglobulin (β₂M), malondialdehyde (MDA), catalase (CAT), reduced glutathione (GSH), superoxide dismutase (SOD) and aspartate aminotransferase (AST). Kidney and liver homogenate was used to measure MDA, GSH and catalase activities. Quantitative real time PCR (qRT-PCR) was used to express Nrf2 and HO-1 in liver, and NF-kB and kidney injury molecule (KIM-1) in kidneys, which are correlated with oxidative stress and inflammation. Capase-3 and Bcl2 genes were examined using immunohistochemical analysis in the kidney and liver. Ethanol administration induced significant alteration in examined liver and kidney markers (AST, ALT, GGT, ALP, total proteins, urea, creatinine and uric acid). Moreover, alcohol administration decreased antioxidant activities at serum and hepatorenal tissues (GSH, catalase and SOD), while MDA was increased as a tissue degradation marker. Inflammatory cytokines, together with genes of oxidative stress markers (Nrf2 and HO-1), were all affected. At cellular levels, apoptotic marker caspase-3 was upregulated, while antiapoptotic marker B-cell lymphoma 2 (Bcl2), was down regulated using immunohistochemical analysis. Of interest, pretreatment with WGO improved the side effects induced by ethanol on hepatic, renal biomarkers and reversed its impact on serum and tissue antioxidant parameters. Nrf2/HO-1 were upregulated, while NFk-B and KIM-1 were downregulated using real time PCR. Immune reactivities of caspase-3 and Bcl2 genes were restored in the protective group. In conclusion, WGO ameliorated ethanol-induced hepatic and renal dysfunction at the biochemical, molecular and cellular levels by regulating some mechanisms that controls oxidative stress, apoptosis, inflammation and anti-apoptotic pathways.

Binge drinking during the adolescence period causes oxidative damage-induced cardiometabolic disorders: A possible ameliorative approach with selenium supplementation

Binge drinking (BD) is the most common alcohol consumption model among adolescents. BD exposure during adolescence disrupts the nervous system function, being involved in the major mortality causes at this age: motor vehicle accidents, homicides and suicides. Recent studies have also shown that BD consumption during adolescence affects liver, renal and cardiovascular physiology, predisposing adolescents to future adult cardiometabolic damage. BD is a particularly pro-oxidant alcohol consumption pattern, because it leads to the production of a great source of reactive oxygen species (ROS) via the microsomal ethanol oxidizing system, also decreasing the antioxidant activity of glutathione peroxidase (GPx). Selenium (Se) is a mineral which plays a pivotal role against oxidation; it forms part of the catalytic center of different antioxidant selenoproteins such as GPxs (GPx1, GPx4, GPx3) and selenoprotein P (SelP). Specifically, GPx4 has an essential role in mitochondria, preventing their oxidation, apoptosis and NFkB-inflamative response, being this function even more relevant in heart's tissue. Se serum levels are decreased in acute and chronic alcoholic adult patients, being correlated to the severity of oxidation, liver damage and metabolic profile. Experimental studies have described that Se supplementation to alcohol exposed mice clearly decreases oxidative and liver damage. However, clinical BD effects on Se homeostasis and selenoproteins' tissue distribution related to oxidation during adolescence are not yet studied. In this narrative review we will describe the use of sodium selenite supplementation as an antioxidant therapy in adolescent BD rats in order to analyze Se homeostasis implication during BD exposure, oxidative balance, apoptosis and inflammation, mainly in liver, kidney, and heart. These biomolecular changes and the cardiovascular function will be analyzed. Se supplementation therapies could be a good strategy to prevent the oxidation, inflammation and apoptosis generated in tissues by BD during adolescence, such as liver, kidney and heart, improving cardiovascular functioning.

Gastroprotective and Antioxidant Properties of Trigonella foenum graecum Seeds Aqueous Extract (Fenugreek) and Omeprazole Against Ethanol-Induced Peptic Ulcer

Trigonella foenum graecum (Fenugreek) is used in traditional phytomedicine for its anti-inflammatory, antiseptic, antidiabetic, and several other therapeutic virtues. The current study was intended to investigate the protecting effects of fenugreek seeds' aqueous extract (FSAE) using experimentally ethanol (EtOH)-induced gastric peptic ulcer in rats, as immense alcohol consumption can lead to gastric ulcer. Sixty adult male Wistar rats were divided into 6 groups of 10 each: control, EtOH (4 g/kg body weight [b.w.]), EtOH + several doses of FSAE (50, 100, and 200 mg/kg b.w.), and EtOH + Omeprazole (OM, 20 mg/kg orally [p.o.]). Animals were p.o. pretreated with FSAE for 21 days and exposed to a single oral administration of EtOH (4 g/kg b.w.) for 2 h. Gastric ulcer in rats was induced with a single dose of EtOH. Ulcer index, malondialdehyde (MDA), hydrogen peroxide (H₂O₂), and thiol groups (-SH) content in stomach, and antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) were measured. Our recorded results showed that EtOH induced gastric damage, evidenced by the level of oxidative stress markers such as MDA and H₂O₂ in rats exposed to EtOH. However, significant increases in the activities of antioxidant enzymes were recorded, such as SOD, CAT, and GPx, and a decrease in nonenzymatic antioxidants, such as (-SH). Moreover, histopathological examinations showed the presence of lesions associated with severe tissue damage in the untreated rats. Interestingly, FSAE meaningfully protects against all gastric damages caused by EtOH. We propose that FSAE exhibits protective effects in EtOH-induced peptic ulcer in rats. This protection might be related to its antioxidant and anti-inflammatory properties as well as its opposite effects on some studied intracellular mediators.

Corticosterone-Mediated Physiological Stress Alters Liver, Kidney, and Breast Muscle Metabolomic Profiles in Chickens

The impact of physiological stress on the metabolomes of liver, kidney, and breast muscle was investigated in chickens. To incite a stress response, birds were continuously administered corticosterone (CORT) in their drinking water at three doses (0, 10, and 30 mg L-1), and they were sampled 1, 5, and 12 days after the start of the CORT administration. To solubilize CORT, it was first dissolved in ethanol and then added to water. The administration of ethanol alone significantly altered branched chain amino acid metabolism in both the liver and the kidney, and amino acid and nitrogen metabolism in breast muscle. CORT significantly altered sugar and amino acid metabolism in all three tissues, but to a much greater degree than ethanol alone. In this regard, CORT administration significantly altered 11, 46, and 14 unique metabolites in liver, kidney, and breast muscle, respectively. Many of the metabolites that were affected by CORT administration, such as mannose and glucose, were previously linked to increases in glycosylation and gluconeogenesis in chickens under conditions of production stress. Moreover, several of these metabolites, such as dimethylglycine, galactose, and carnosine were also previously linked to reduced quality meat. In summary, the administration of CORT in chickens significantly modulated host metabolism. Moreover, results indicated that energy potentials are diverted from muscle anabolism to muscle catabolism and gluconeogenesis during periods of stress.

10-Dehydrogingerdione ameliorates renal endoplasmic reticulum/oxidative stress and apoptosis in alcoholic nephropathy induced in experimental rats

BACKGROUND

Chronic alcoholism induces kidney injury (KI), leading to increased mortality in alcoholic hepatitis patients. Endoplasmic reticulum stress (ER) represents the main initiator of kidney diseases and alcoholic nephropathy.

AIMS

We used alcoholic nephropathy rat model followed by 10-dehydrogingerdione (10-DHGD) intake as potential modulator. This is to focus on ER/oxidative stress/inflammatory and apoptotic pathways involvement.

MAIN METHOD

Alcoholic nephropathy was induced by alcohol administration (3.7 g/kg/body weight) orally and daily for 45 days. 10-DHGD (10 mg/kg/day) was administered either alone or along with alcohol.

KEY FINDINGS

Our results demonstrated significant increase in kidney function parameters like f creatinine, urea, uric acid, and blood urea nitrogen (BUN) levels. Renal ER/oxidative stress markers such as cytochrome P450 family two subfamily E member 1 (CYP2E1), C/EBP homologous protein (CHOP), and endoplasmic glucose-regulated protein 78 (GRP-78) demonstrated also significant increase. Inflammatory mediators like nuclear factor-kappa B (NF-kB), tumor necrosis factor-α (TNF-α), and transforming growth factor-β (TGF-β along with apoptotic marker caspase-3 behaved similarly. Antioxidant molecules like reduced glutathione (GSH), superoxide dismutase (SOD), and catalase demonstrated marked decrease.

SIGNIFICANCE

10-DHGD administration resulted in significant modulation represented by an enhancement in the kidney functions and the histopathological patterns in a conclusion of its potential to ameliorate the pathological changes (kidney injury) induced by alcohol intake.

Exploration of the optimal strategy for dietary calcium intervention against the toxicity of liver and kidney induced by cadmium in mice: An in vivo diet intervention study

Cadmium (Cd) is a toxic non-essential element, while calcium (Ca) is an essential element with high chemical similarity to Cd. Dietary intake is the major Cd exposure pathway for non-smokers. A multi-concentration dietary intervention experiment was designed to explore the optimum concentration of Ca in diet with obvious protective effects against the toxicity of livers and kidneys induced by Cd in mice. The mice were divided into six groups with different concentrations of Cd and Ca in their food: control-group (no Cd or Ca), Ca-group (100 g/kg Ca, without Cd), Cd-group (2 mg/kg Cd, without Ca), Ca_L+Cd-group (2 mg/kg Cd, 2 g/kg Ca), Ca_M+Cd-group (2 mg/kg Cd, 20 g/kg Ca) and Ca_H+Cd-group (2 mg/kg Cd, 100 g/kg Ca). The organ indexes, oxidative stress biomarkers, lesions and Cd concentrations were detected after a 30-day exposure period. Results showed that serum Aspartate Aminotransferase (AST) level in Ca_H+Cd-group was significantly lower than that in Cd-group, while close to that in control-group. The contents of Serum Blood Urea Nitrogen (BUN) in different groups showed the same trend. Concentrations of all oxidative stress biomarkers (GSH-Px, SOD, CAT, GSH and MDA) in Ca_H+Cd-group were close to the normal levels of control-group while significantly different from those in Cd-group. The only exception was the Malondialdehyde (MDA) levels in kidneys. This study suggests that Ca plays a protective role in relieving the Cd-induced toxicity of livers and kidneys and a concentration of 100 g/kg for Ca in diet showed the best protective effects. These findings could provide a clue for further studies concerning human diet intervention for Cd control.

Alcohol consumption and serum uric acid are synergistically associated with renal dysfunction among community-dwelling persons

Background

Serum uric acid (SUA) is a key risk factor contributing to renal failure, a serious public health problem. However, few studies have examined whether the interactive relationship between alcohol consumption and SUA is independently associated with the estimated glomerular filtration rate (eGFR).

Methods

Our sample comprised 742 men aged 69 ± 11 years (mean ± standard deviation) and 977 women aged 69 ± 10 years from a rural area. We cross‐sectionally examined the relationships between the confounding factors of alcohol consumption and SUA with renal function denoted by eGFR estimated using CKD‐EPI (Chronic Kidney Disease Epidemiology Collaboration) equations modified by a Japanese coefficient.

Results

In both genders, eGFR increased with a rise in alcohol consumption. This tendency was more pronounced in participants with hyperuricemia, where SUA was greater than 7.0 mg/dL in men and greater than 6.0 mg/dl in women (men: F = 41.98, p < 0.001; women: F = 41.98, p < 0.001). A multiple linear regression analysis showed that alcohol consumption (men: β = 0.112, p < 0.001; women: β = 0.060, p = 0.011) and SUA (men: β = −0.282, p < 0.001; women: β = 0.317, p < 0.001) were significantly and independently related to eGFR. Further, the interactive relationship between alcohol consumption and SUA (men: F = 6.388, p < 0.001; women: F = 5.368, p < 0.001) was a significant and independent indicator of eGFR.

Conclusions

These results suggested that alcohol consumption and SUA were synergistically associated with renal dysfunction among community‐dwelling persons.

Causal effect of alcohol use on the risk of end-stage kidney disease and related comorbidities: a Mendelian randomization study

BACKGROUND

An inverse observational association between alcohol use and the risk of chronic kidney disease (CKD) or end-stage kidney disease (ESKD) has been reported. The causal effect of alcohol use on the risk of ESKD warrants additional investigation.

METHODS

The study was an observational cohort study investigating the UK Biobank and performed Mendelian randomization (MR) analysis. Amounts of alcohol use were collected using a touchscreen questionnaire. In the observational analysis, 212,133 participants without prevalent ESKD were studied, and the association between alcohol use and the risk of prevalent CKD or incident ESKD was investigated. The genetic analysis included 337,138 participants of white British ancestry. For one-sample MR, an analysis based on a polygenic risk score (PRS) was conducted with genetically predicted alcohol intake. The MR analysis investigated ESKD outcome and related comorbidities.

RESULTS

Lower alcohol use was observationally associated with a higher risk of prevalent CKD or incident ESKD. However, the genetic risk of CKD was significantly associated with lower alcohol use, suggesting reverse causation. A higher PRS for alcohol use was significantly associated with a higher risk of ESKD (per units of one phenotypical alcohol drink; adjusted odds ratio of 1.16 [95% confidence interval, 1.02-1.31]) and related comorbidities, including hypertension, diabetes mellitus, obesity, and central obesity.

CONCLUSION

The inverse observational association between alcohol use and the risk of CKD or ESKD may have been affected by reverse causation. Our study supports a causal effect of alcohol use on a higher risk of ESKD and related predisposing comorbidities.

Antrodin A from Antrodia camphorata modulates the gut microbiome and liver metabolome in mice exposed to acute alcohol intake

This study aimed to investigate the protective effect of Antrodin A (AdA) from Antrodia camphorata (A. camphorata) mycelium on alcohol-induced gut microbiota and liver metabolomic disorders. In acute alcoholic liver injury mice, AdA ameliorated alcoholic exposure-induced hepatic lipid deposition (TC and TG), oxidative stress (MDA), inflammation (TNF-α, IL-1β, IL-6, IL-17 and IFN-γ), and liver damage via modulating microbiome and metabolomic responses. AdA restored the composition of intestinal flora with an increase in the relative abundance of Lactobacillus and Dubosiella and a decrease in Clostridium_sensu_stricto_1, Lachnospiraceae_NK4A136_group, Prevotellaceae_NK3B31_group, and Prevotellaceae_UCG-001. Besides, AdA favorably regulated alcohol-induced metabolic disorders, including glutathione metabolism (S-(2-hydroxyethyl)glutathione and glutathione oxidized), ascorbate and aldarate metabolism (l-ascorbic acid), and taurine and hypotaurine metabolism (taurine). In conclusion, AdA in A. camphorata is a beneficial active ingredient to treat the microbiomic and metabolic disturbance induced by alcohol intake.

Effect of alcohol consumption on kidney function: population-based cohort study

The association between alcohol consumption and kidney function is intriguing, but study results are mixed and controversial. We examined the association of alcohol consumption with the overall change in kidney function over 12 years. We analyzed data from a population-based cohort that was part of the Korean Genome and Epidemiology Study. Primary exposure was total alcohol intake (non-drinkers, 0 to < 10 g/day, 10 to < 30 g/day, and ≥ 30 g/day). Main outcome was decline in kidney function over 12 years. Our study included 5729 participants (mean [SD] age, 51 [8] years; 46% males). Compared to non-drinkers, higher alcohol intake groups had lesser reduction in estimated glomerular filtration rate (eGFR) over 12 years; fully adjusted beta coefficients and 95% confidence intervals were 0.45 (− 0.27, 1.18), 1.87 (0.88, 2.87), and 3.08 (1.93, 4.24) for participants with alcohol intake of < 10, 10 to < 30, and ≥ 30 g/day, respectively. However, this association was attenuated among women, smoker, and age ≥ 60 year. Compared with not drinking, more frequent alcohol consumption and binge drinking were associated with lesser reduction in eGFR. Our findings suggest that alcohol consumption may have a favorable effect on kidney function among the general population.

Ginger (Zingiber officinale roscoe) extract could upregulate the renal expression of NRF2 and TNFα and prevents ethanol-induced toxicity in rat kidney

OBJECTIVE

Ginger has protective effects on the kidney, however the molecular mechanism of this effect has not yet been fully elucidated. Therefore, this work studied molecular mechanisms of ginger effects on ethanol-induced kidney injury.

MATERIALS AND METHODS

Twenty-four male Sprague-Dawley rats were randomly divided into four groups: control, ginger (1 g/kg/day ginger extract by oral gavage), ethanol (4 g/kg/day ethanol by oral gavage) and ginger-ethanol group and treated daily for 28 days. Kidney function, expression of nuclear factor erythroid 2-related factor 2 (NRF2) and tumor necrosis factor (TNF)-α genes and oxidative stress parameters in kidney tissue, were evaluated. Total phenolic content (TPC) and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity of ginger extract were also evaluated.

RESULTS

Hydroethanolic extract of ginger showed a good level of DPPH scavenging activity and TPC. In the ethanol group, serum level of urea, creatinine and uric acid and the expression of NRF2 and TNF-α significantly increased compared to control group, while co-treatment with ginger in ginger+ethanol group significantly ameliorated them compared to the ethanol group. Ethanol exposure significantly reduced the activity of superoxide dismutase  (SOD), glutathione peroxidase (GPx) and catalase (CAT) compared to the control values ,while the level of malondialdehyde (MDA) significantly increased. Ginger significantly ameliorated the level of MDA and activity of SOD, GPx and CAT in the ginger-ethanol group compared to the ethanol group.

CONCLUSION

The results showed that ginger's protective effects against ethanol renotoxicity were mediated via enhancing the NRF2 and TNF-α expression.

Modifiable Lifestyle Factors for Primary Prevention of CKD: A Systematic Review and Meta-Analysis

BACKGROUND

Despite increasing incidence of CKD, no evidence-based lifestyle recommendations for CKD primary prevention apparently exist.

METHODS

To evaluate the consistency of evidence associating modifiable lifestyle factors and CKD incidence, we searched MEDLINE, Embase, CINAHL, and references from eligible studies from database inception through June 2019. We included cohort studies of adults without CKD at baseline that reported lifestyle exposures (diet, physical activity, alcohol consumption, and tobacco smoking). The primary outcome was incident CKD (eGFR<60 ml/min per 1.73 m²). Secondary outcomes included other CKD surrogate measures (RRT, GFR decline, and albuminuria).

RESULTS

We identified 104 studies of 2,755,719 participants with generally a low risk of bias. Higher dietary potassium intake associated with significantly decreased odds of CKD (odds ratio [OR], 0.78; 95% confidence interval [95% CI], 0.65 to 0.94), as did higher vegetable intake (OR, 0.79; 95% CI, 0.70 to 0.90); higher salt intake associated with significantly increased odds of CKD (OR, 1.21; 95% CI, 1.06 to 1.38). Being physically active versus sedentary associated with lower odds of CKD (OR, 0.82; 95% CI, 0.69 to 0.98). Current and former smokers had significantly increased odds of CKD compared with never smokers (OR, 1.18; 95% CI, 1.10 to 1.27). Compared with no consumption, moderate consumption of alcohol associated with reduced risk of CKD (relative risk, 0.86; 95% CI, 0.79 to 0.93). These associations were consistent, but evidence was predominantly of low to very low certainty. Results for secondary outcomes were consistent with the primary finding.

CONCLUSIONS

These findings identify modifiable lifestyle factors that consistently predict the incidence of CKD in the community and may inform both public health recommendations and clinical practice.

Alcoholic hepatitis and metabolic disturbance in female mice: a more tractable model than Nrf2-/- animals

Alcoholic hepatitis (AH) is the dramatic acute presentation of alcoholic liver disease, with a 15% mortality rate within 28 days in severe cases. Research into AH has been hampered by the lack of effective and reproducible murine models that can be operated under different regulatory frameworks internationally. The liquid Lieber-deCarli (LdC) diet has been used as a means of ad libitum delivery of alcohol but without any additional insult, and is associated with relatively mild liver injury. The transcription factor nuclear factor-erythroid 2-related factor 2 (Nrf2) protects against oxidative stress, and mice deficient in this molecule are suggested to be more sensitive to alcohol-induced injury. We have established a novel model of AH in mice and compared the nature of liver injury in C57/BL6 wild-type (WT) versus Nrf2-/- mice. Our data showed that both WT and Nrf2-/- mice demonstrate robust weight loss, and an increase in serum transaminase, steatosis and hepatic inflammation when exposed to diet and ethanol. This is accompanied by an increase in peripheral blood and hepatic myeloid cell populations, fibrogenic response and compensatory hepatocyte regeneration. We also noted characteristic disturbances in hepatic carbohydrate and lipid metabolism. Importantly, use of Nrf2-/- mice did not increase hepatic injury responses in our hands, and female WT mice exhibited a more-reproducible response. Thus, we have demonstrated that this simple murine model of AH can be used to induce an injury that recreates many of the key human features of AH - without the need for challenging surgical procedures to administer ethanol. This will be valuable for understanding of the pathogenesis of AH, for testing new therapeutic treatments or devising metabolic approaches to manage patients whilst in medical care.This article has an associated First Person interview with the joint first authors of the paper.

Taurine suppresses ROS-dependent autophagy via activating Akt/mTOR signaling pathway in calcium oxalate crystals-induced renal tubular epithelial cell injury

Oxidative stress and autophagy are the key promoters of calcium oxalate (CaOx) nephrolithiasis. Taurine is an antioxidant that plays a protective role in the pathogenesis of kidney disease. Previous studies found that taurine suppressed cellular oxidative stress, and inhibited autophagy activation. However, the effect of taurine on CaOx kidney stone formation remains unknown. In the present work, we explored the regulatory effects of taurine on CaOx crystals-induced HK-2 cell injury. Results showed that pretreatment with taurine significantly enhanced the viability of HK-2 cells and ameliorated kidney tissue injury induced by CaOx crystals. Taurine also markedly reduced the levels of inflammatory cytokines, apoptosis, and CaOx crystals deposition. Furthermore, we observed that taurine supplementation alleviated CaOx crystals-induced autophagy. Mechanism studies showed that taurine reduced oxidative stress via increasing SOD activity, reducing MDA concentration, alleviating mitochondrial oxidative injury, and decreasing the production of intracellular ROS. Taurine treatment also effectively activated Akt/mTOR signaling pathway in CaOx crystals-induced HK-2 cells both in vitro and in vivo. In summary, the current study shows that taurine inhibits ROS-dependent autophagy via activating Akt/mTOR signaling pathway in CaOx crystals-induced HK-2 cell and kidney injury, suggesting that taurine may serve as an effective therapeutic agent for the treatment of CaOx nephrolithiasis.

Nephro-protective activity of wheatgrass juice against alcohol-induced oxidative damage in rats

The present study is an attempt to check the protective effect of fresh wheatgrass juice (WJ) as a potential therapeutic agent against alcohol-induced oxidative/nitrosative stress leading to nephrotoxicity in rats. Administration of 20% ethanol (5 g/kg b.wt/day) for 60 days resulted in a significant rise in the plasma concentrations of urea and creatinine with decreased levels of uric acid. Besides, a significant decrease in plasma electrolyte/mineral levels along with decreased activity of Na+/K+-ATPase activity was recorded in alcohol administered rats. In alcohol administered rats augmented lipid peroxidation (thio-barbituric acid reactive substance - TBARS) and nitric oxide (NOx) reflects the increased oxidative stress and nitrosative stress, moreover, we noticed a concomitant decrease in the levels of reduced glutathione (GSH) with decreased activities of antioxidant enzyme machinery viz., superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione s-transferase (GST). Administration of WJ to the alcoholic rats significantly restored the plasma biochemical markers and the kidney antioxidant status near to control group animal levels. These findings were further confirmed by the kidney histopathological studies, wherein the protective effect of WJ treatment in retaining the morphological features of the renal tissue in spite of the alcohol administration was evident. The rich repertoire of phenolic compounds present in the WJ from the freshly sprouted seeds synergistically protected the kidney from alcohol-induced damage.

Alcohol promotes renal fibrosis by activating Nox2/4-mediated DNA methylation of Smad7

Alcohol consumption causes renal injury and compromises kidney function. The underlying mechanism of the alcoholic kidney disease remains largely unknown. In the present study, an alcoholic renal fibrosis animal model was first employed which mice received liquid diet containing alcohol for 4 to 12 weeks. The Masson's Trichrome staining analysis showed that kidney fibrosis increased at week 8 and 12 in the animal model that was further confirmed by albumin assay, Western blot, immunostaining and real-time PCR of fibrotic indexes (collagen I and α-SMA). In vitro analysis also confirmed that alcohol significantly induced fibrotic response (collagen I and α-SMA) in HK2 tubular epithelial cells. Importantly, both in vivo and in vitro studies showed alcohol treatments decreased Smad7 and activated Smad3. We further determined how the alcohol affected the balance of Smad7 (inhibitory Smad) and Smad3 (regulatory Smad). Genome-wide methylation sequencing showed an increased DNA methylation of many genes and bisulfite sequencing analysis showed an increased DNA methylation of Smad7 after alcohol ingestion. We also found DNA methylation of Smad7 was mediated by DNMT1 in ethyl alcohol (EtOH)-treated HK2 cells. Knockdown of Nox2 or Nox4 decreased DNMT1 and rebalanced Smad7/Smad3 axis, and thereby relieved EtOH-induced fibrotic response. The inhibition of reactive oxygen species by the intraperitoneal injection of apocynin attenuated renal fibrosis and restored renal function in the alcoholic mice. Collectively, we established novel in vivo and in vitro alcoholic kidney fibrosis models and found that alcohol induces renal fibrosis by activating oxidative stress-induced DNA methylation of Smad7. Suppression of Nox-mediated oxidative stress may be a potential therapy for long-term alcohol abuse-induced kidney fibrosis.

Renoprotective effect of Capsicum annum against ethanol-induced oxidative stress and renal apoptosis

The present study explored the ameliorative potency of aqueous extract of Capsicum annum (AqCA), against oxidative imbalance and renal toxicity induced by ethanol. Randomly grouped male Wistar rats (n = 6), were marked as ethanol-treated (2 g/kg bw, i.p.), CA₁₂₅ (125 mg/kg bw, i.p.), CA₂₅₀ (250 mg/kg bw, i.p.), ethanol pre-treated with CA (similar doses), and control (0.5 ml normal saline, i.p.), and treated for 30 consecutive days. Biochemical analysis of tissue and serum parameters was performed, along with histopathological and histochemical studies. Also, we performed TUNEL assay and western blotting for our experimental groups. Statistical analysis revealed significant (p ≤ .001) alteration in the levels of antioxidant enzymes, serum urea, creatinine, pro-inflammatory cytokines, and cleaved caspases, along with histopathological alterations in the ethanol-treated group. Prior treatment with AqCA prevented ethanol-induced alterations in tissue and serum parameters. These findings indicate that the extract of CA can protect renal cells from ethanol-induced damage by inhibiting oxidative stress, inflammatory response, and apoptosis. PRACTICAL APPLICATIONS: Chronic alcohol consumption is a major public health concern that leads to various diseases and social problems as well. It affects both the affluent and non-affluent society equally. Alcohol (ethanol) is a renowned hepato-toxicant and a well-documented risk factor for oxidative stress, with less known effect on the kidney. Thus, it is essential to investigate the effect of alcohol metabolism on the kidney to find a remedy to prevent it. The present investigation depicts the anti-oxidative and anti-inflammatory role of Capsicum annum against ethanol-induced renal damage. The outcome of this study can be utilized in the future for phytotherapeutic herbal drug formulation. Besides, the bioactive components identified in the study can be further explored by researchers or pharmaceutical corporates for potential therapeutic purpose against renal impairment.

At-Risk Drinking Is Independently Associated With Acute Kidney Injury in Critically Ill Patients

OBJECTIVES

Unhealthy use of alcohol and acute kidney injury are major public health problems, but little is known about the impact of excessive alcohol consumption on kidney function in critically ill patients. We aimed to determine whether at-risk drinking is independently associated with acute kidney injury in the ICU and at ICU discharge.

DESIGN

Prospective observational cohort study.

SETTING

A 21-bed polyvalent ICU in a university hospital.

PATIENTS

A total of 1,107 adult patients admitted over a 30-month period who had an ICU stay of greater than or equal to 3 days and in whom alcohol consumption could be assessed.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We assessed Kidney Disease Improving Global Outcomes stages 2-3 acute kidney injury in 320 at-risk drinkers (29%) and 787 non-at-risk drinkers (71%) at admission to the ICU, within 4 days after admission and at ICU discharge. The proportion of patients with stages 2-3 acute kidney injury at admission to the ICU (42.5% vs 18%; p < 0.0001) was significantly higher in at-risk drinkers than in non-at-risk drinkers. Within 4 days and after adjustment on susceptible and predisposing factors for acute kidney injury was performed, at-risk drinking was significantly associated with acute kidney injury for the entire population (odds ratio, 2.15; 1.60-2.89; p < 0.0001) in the subgroup of 832 patients without stages 2-3 acute kidney injury at admission to the ICU (odds ratio, 1.44; 1.02-2.02; p = 0.04) and in the subgroup of 971 patients without known chronic kidney disease (odds ratio, 1.92; 1.41-2.61; p < 0.0001). Among survivors, 22% of at-risk drinkers and 9% of non-at-risk drinkers were discharged with stages 2-3 acute kidney injury (p < 0.001).

CONCLUSIONS

Our results suggest that chronic and current alcohol misuse in critically ill patients is associated with kidney dysfunction. The systematic and accurate identification of patients with alcohol misuse may allow for the prevention of acute kidney injury.

Effect of imidazoline-1 receptor agonists on renal dysfunction in rats associated with chronic, sequential fructose and ethanol administration

Insulin resistance and chronic alcoholism are risk factors for renal dysfunction. This study investigated the therapeutic effects of two imidazoline-1 receptor (I1R) agonists on renal dysfunction in rats after chronic, sequential fructose and ethanol administration. Daily drinking water was supplemented with fructose (10%, w/v) for 12 weeks and then with ethanol (20%, v/v) for another 8 weeks. Rats were treated with rilmenidine and clonidine in the last two weeks of the study. Blood glucose and serum insulin (sIns) levels, lipid profiles, kidney function and renal histopathology were evaluated at the end of the experiment. Additionally, renal gene expression of nischarin, phosphatidylcholine-specific phospholipase C (PC-PLC) and prostaglandin E2 (PGE2) were measured. Renal levels of superoxide dismutase (SOD), malondialdehyde (MDA), myeloperoxidase (MPO), inducible nitric oxide synthase (iNOS) and total NO (tNO) were detected, and we determined the relative renal gene expression levels of alpha smooth muscle actin (α-SMA), hydroxyproline, interleukin 10 (IL-10), tumour necrosis factor alpha (TNF-α) and caspase-3. The results showed significant deterioration of blood glucose, sIns, lipid profiles, kidney function and renal histopathology in fructose/ethanol-fed rats. Additionally, markers of inflammation, fibrosis, apoptosis and oxidative stress were upregulated. The administration of rilmenidine or clonidine significantly improved blood glucose and sIns levels and reduced renal dysfunction. Our work showed that chronic, sequential fructose and ethanol administration induced fasting hyperglycaemia and renal impairment, and these effects were ameliorated by I1R agonists.

Alcohol Consumption Can be a "Double-Edged Sword" for Chronic Kidney Disease Patients

Excessive drinking of alcohol is becoming a worldwide problem, and people have recognized that there exists a close relationship between chronic kidney disease (CKD) and alcohol consumption. However, there are many inconsistencies between experimental and clinical studies on alcohol consumption and kidney damage. The possible reason for this contradictory conclusion is the complex drinking pattern of humans and some bioactivators in wine. In addition, the design itself of the clinical studies can also produce conflicting interpretations of the results. Considering the benefits of light-to-moderate alcohol consumption, we recommend that CKD patients continue light-to-moderate drinking, which is beneficial to them. Because alcohol consumption can lead to adverse events, we do not advise non-drinkers to start to drink. Although light-to-moderate alcohol consumption may not pose a risk to patients with CKD, the patients’ condition needs to be considered. Consumption of even small amounts of alcohol can be associated with increased death risk. Additional clinical and experimental studies are needed to clarify the effect of alcohol on the kidneys and alcohol consumption on CKD patients.

Dexmedetomidine protects against lipopolysaccharide-induced early acute kidney injury by inhibiting the iNOS/NO signaling pathway in rats

Increasing evidence has demonstrated that dexmedetomidine (DEX) possesses multiple pharmacological actions. Herein, we explored the protective effect and potential molecular mechanism of DEX on lipopolysaccharide (LPS)-induced early acute kidney injury (AKI) from the perspective of antioxidant stress. We found that DEX (30 μg/kg, i.p.) ameliorated the renal dysfunction and histopathological damage (tubular necrosis, vacuolar degeneration, infiltration of inflammatory cells and cast formation) induced by LPS (10 mg/kg). DEX also attenuated renal oxidative stress remarkably in LPS-induced early AKI, as evidenced by reduction in production of reactive nitrogen species, decreasing malondialdehyde levels, as well as increasing superoxide dismutase activity and glutathione content. DEX prevented activator protein-1 translocation, inhibited phosphorylation of I-kappa B (IκB) and activation of nuclear factor kappa B (NF-κB) in LPS-induced early AKI, as assessed by real-time quantitative polymerase chain reaction and protein levels of c-Jun, c-Fos, IκB and NF-κB. Notably, DEX pretreatment had the same effect as intraperitoneal injection of an inhibitor of inducible nitric oxide synthase inhibitor (1400W; 15 mg/kg), and inhibited the activity of renal inducible nitric oxide synthase (iNOS) and decreased the expression of iNOS mRNA and NO production. However, the protective effect of DEX on LPS-induced early AKI was reversed by the alpha 2 adrenal receptor (α₂-AR) inhibitor atipamezole, whereas the imidazoline receptor inhibitor idazoxan did not. Taken together, DEX protects against LPS-induced early AKI in rats by inhibiting the iNOS/NO signaling pathway, mainly by acting on α₂-ARs instead of IRs.

Preventive or Curative Administration of Taurine Regulates Lipid Metabolism in the Liver of Rats with Alcoholic Liver Disease

Excessive consumption causes alcoholic liver disease (ALD), which injures hepatocytes and induces imbalance of lipid metabolism. Taurine is known to protect the liver from various liver injuries, and relieve lipid profile. Our previous studies also found that taurine can prevent or cure ALD, reduce fat deposition, but the mechanism remains unclear. In the present study, ALD rat model was established by administration of alcohol, pyrazole and high fat diet. Two percent taurine was administered at the same time or after ALD model establishment. Serum activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), serum and hepatic TC, TG, HDL-C and LDL-C were analyzed. Real-Time RT-PCR was conducted to detect the mRNA expressions of fatty acid synthetase (FAS), acetyl-CoA catboxylase (ACC), carnitine palmitoyl transferase 1 (CPT-1), 3-Hydroxy-3-methyl glutaric acid acyl Coenzyme A reductase (HMGCR), peroxisome proliferators activated receptor α (PPARα) and sterol regulatory element-binding protein 1c (SREBP-1c). The results showed that serum ALT, AST, serum and hepatic TC, TG and LDL-C were higher, while HDL-C in ALD model rats was lower than normal rats, the changes of which can be significantly relieved by taurine administration. mRNA expressions of ACC, FAS, CPT-1, HMGCR, PPARα and SREBP-1c which were significantly changed by ethanol can also be regulated by taurine. The results indicated that taurine can prevent and repair hepatic injury of ALD rats and balance lipid metabolism indexes in the liver, the mechanisms may involves in the regulation of related enzymes and transcriptional regulators participated in lipid metabolism.

Falcaria vulgaris Extract Attenuates Ethanol-induced Renal Damage by Reducing Oxidative Stress and Lipid Peroxidation in Rats

Background:

Alcohol consumption is capable of producing free radicals and inducing disturbance in body antioxidant. Falcaria vulgaris (F. vulgaris) is a vegetable and it has beneficial antioxidant effects.

Materials and Methods:

Forty-eight Wistar rats were divided randomly into eight groups (n = 6): control normal (saline) and ethanol (5g EtOH/kg body weight/24h) control groups, F. vulgaris groups (50, 100, and 150mg/kg), and F. vulgaris + ethanol treated groups (50, 100, and 150mg/kg). Treatments were administered intraperitoneally and through gavage daily for 12 weeks. Parameters related to the function and the histology of the kidneys were evaluated and statistically analyzed from kidney and blood serum samples with respect to the groups.

Results:

Ethanol administration increased significantly Bowman’s space, qualitative histopathology indices, kidney malondialdehyde (MDA) level, blood urea nitrogen (BUN), creatinine, and nitrite oxide levels and decreased significantly total antioxidant capacity (TAC) level and diameter and number of renal corpuscles compared to that in the control normal group (P < 0.001). The F. vulgaris and F. vulgaris + ethanol treatments in a dose-dependent manner reduced significantly Bowman’s space, qualitative histopathology indices, kidney MDA level, BUN, creatinine, and nitrite oxide levels and increased significantly TAC level and diameter and number of renal corpuscles compared to that in the ethanol normal group (P < 0.001).

Conclusion:

It seems that F. vulgaris administration in a dose-dependent manner improved kidney injury induced by ethanol in rats.

Taurine Reverses Atrial Structural Remodeling in Ach-Cacl2 Induced Atrial Fibrillation Rats

Taurine has been reported to have anti-arrhythmia effects, but the anti-atrial fibrillation (AF) effects and its mechanism remain incompletely understood. In the present study, the therapy effects and partly mechanisms were investigated. AF animal model was established by intravenous administered with the mixture of acetylcholine (Ach) and CaCl2 (66 μg/mL + 10 mg/mL) (i.v.) for 7 days. The actions of taurine (99 mg/kg∙d, introgastric administration) on the levels of Hs-CRP, IL-6, TNF-α, MMP-9, AngII, the extent of the fibrosis and ultrastructural changes in left atrial were studied. The data showed that the serum levels of TNF-α, IL-6, AngII and the plasma levels of Hs-CRP and MMP-9 were significantly elevated in automatic recovery group relative to the control group (p < 0.01), which were all decreased by taurine administration (p < 0.01) similar to Verapamil treatment. Masson's trichrome staining of the left atrial tissue showed an obvious interstitial fibrosis in rats of automatic recovery group. The alteration could be reversed by additional taurine. Electron microscopy revealed that taurine administration could significantly alleviate the ultrastructural damage of atrial cells, and the effects were similar to the Verapamil treatment. In conclusion, the results suggested that taurine could inhibit the structural remodeling of AF in rats partly by decreasing the levels of inflammatory factors and profibrotic molecules, attenuating the extent of myocardial fibrosis and protecting the integrity of myocardial ultrastructure.

Chronic ethanol ingestion induces glomerular filtration barrier proteins genes expression alteration and increases matrix metalloproteinases activity in the kidney of rats

Background

Chronic alcohol ingestion-induced kidney structure and function alterations are very well known, but the precise underlying molecular mediators involved in ethanol-induced kidney abnormalities remain elusive. The aim of this study was to investigate the effect of chronic ethanol exposure on matrix metalloproteinase 2, 9 (MMP), glomerular filtration barrier proteins (nephrin and podocin), as well as vascular endothelial growth factor receptor 1, 2 (VEGFRs) isoforms gene expression in the kidney of rats.

Methods

Sixteen male Wistar rats with an initial body weight of 220 ± 10 g were divided into the following two groups: (1) control and (2) ethanol (4.5 g/kg BW).

Results

After 6 weeks of treatment, the results revealed a significant increase in isoforms VEGFR1 and VEGFR2 of VEGFR gene expression, significant increases of MMP2 and MMP9 activities, as well as significant decrease of nephrin and podocin gene expressions in the ethanol group, compared with that in the control group.

Conclusion

These findings indicate that ethanol-induced kidney abnormalities may be in part associated with alteration in expressions of VEGFRs, nephrin, and podocin and in increasing activities of MMP2 and MMP9 as key molecular mediators in the kidney function.

Effects of co-exposure to atrazine and ethanol on the oxidative damage of kidney and liver in Wistar rats

Both ethanol (EtoH) and atrazine (ATZ) have hepatic and nephro-toxic effects in rats. In the present study, the toxicity of EtoH (5 g kg-1) on the kidney and liver in the absence or in the presence of different doses of ATZ (50, 100, 300 mg kg-1) was evaluated after 21 days in rats. Results showed that the mixture effects on catalase and superoxide dismutase activities were more severe in both tissues compared to EtoH alone, especially as the dose of ATZ was increased. Hepatic malondialdehyde level (an index of lipid peroxidation) was increased from 20.32% in the EtoH +50 mg kg-1 ATZ-treated rats to 34% in the EtoH +300 mg kg-1 ATZ-treated rats compared to the EtoH values. Renal malondialdehyde values remain as high as 81% in the EtoH-treated rats and the different combine exposure groups. Furthermore, as the dose of ATZ in the mixture was increased, serum uric acid level increased compared to the EtoH values. When the EtoH +300 mg kg-1 ATZ-animals were pretreated with curcumin (an antioxidant), the histopathological changes and peroxidative damages in both tissues were blocked. The exposure of EtoH-treated rats to ATZ enhanced renal and hepatic peroxidative damages in rats.

Cytochrome P450-2E1 is involved in aging-related kidney damage in mice through increased nitroxidative stress

The aim of this study was to investigate the role of cytochrome P450-2E1 (CYP2E1) in aging-dependent kidney damage since it is poorly understood. Young (7 weeks) and aged female (16-17 months old) wild-type (WT) and Cyp2e1-null mice were used. Kidney histology showed that aged WT mice exhibited typical signs of kidney aging such as cell vacuolation, inflammatory cell infiltration, cellular apoptosis, glomerulonephropathy, and fibrosis, along with significantly elevated levels of renal TNF-α and serum creatinine than all other groups. Furthermore, the highest levels of renal hydrogen peroxide, protein carbonylation and nitration were observed in aged WT mice. These increases in the aged WT mice were accompanied by increased levels of iNOS and mitochondrial nitroxidative stress through altered amounts and activities of the mitochondrial complex proteins and significantly reduced levels of the antioxidant glutathione (GSH). In contrast, the aged Cyp2e1-null mice exhibited significantly higher antioxidant capacity with elevated heme oxygenase-1 and catalase activities compared to all other groups, while maintaining normal GSH levels with significantly less mitochondrial nitroxidative stress compared to the aged WT mice. Thus, CYP2E1 is important in causing aging-related kidney damage most likely through increasing nitroxidative stress and that CYP2E1 could be a potential target in preventing aging-related kidney diseases.

Protective effects of orange (Citrus sinensis L.) peel aqueous extract and hesperidin on oxidative stress and peptic ulcer induced by alcohol in rat

BACKGROUND

Massive alcohol drinking can lead to gastric ulcer. In the present study we investigated the gastroprotective effect of Citrus sinensis peel aqueous extract (CSPE) and Hesperidin (H) in ethanol (EtOH) induced oxidative stress and peptic ulcer in rats.

METHODS

Seventy adult male Wistar rats were divided into seven groups of 10 each: control, EtOH (4 g/kg b.w.), EtOH + various doses of CSPE (100, 200 and 400 mg/kg, b.w.), EtOH + Hesperidin (50 mg/kg, p.o.) and EtOH + Omeprazole (OM, 20 mg/kg, p.o.). Animals were perorally (p.o.) pre-treated with CSPE during 15 days and intoxicated with a single oral administration of EtOH (4 g/kg b.w.) during 2 h. Gastric ulcer was induced in rats with a single dose of ethanol (EtOH). Ulcer index, gene expression of gastric cyclooxygenase-2 (COX-2), tumor necrosis factor alpha (TNF-α), malondialdhyde (MDA), hydrogen peroxide H2O2 and Thiol groups (-SH) content in stomach and antioxidant enzymes superoxide dismutase (SOD), catalase (CAT) and gluthation peroxidise (GPx) were measured. Furthermore, histopathological examinations were performed.

RESULTS

The results showed that ethanol induced gastric damage, improving oxidative stress markers level such as MDA (121 ± 4.45 nmol/mg proteins) and H2O2 (24.62 ± 1.04 μmol/mg proteins), increased pro-inflammatory cytokine (TNF-α level), as well as the expression of COX-2 in the ethanol group. However, a significant depletion of enzymatic and non-enzymatic antioxidants were observed, such as, GPx (72%), SOD (57.5%), CAT (41.6%) and -SH (50%). The lesions were associated with severe histopathological damage. The both Citrus sinensis peel aqueous extract (CSPE) and hesperidin significantly protect against all gastric damages caused by ethanol administration in rats.

CONCLUSIONS

We propose that CSPE and hesperidin exhibit protective effects in EtOH-induced peptic ulcer in rat. This protection might be related in to part its antioxidant properties as well as its opposite effects on some studied intracellular mediators.

Gene and protein expressions and metabolomics exhibit activated redox signaling and wnt/β-catenin pathway are associated with metabolite dysfunction in patients with chronic kidney disease

Changes in plasma concentration of small organic metabolites could be due to their altered production or urinary excretion and changes in their urine concentration may be due to the changes in their filtered load, tubular reabsorption, and/or altered urine volume. Therefore, these factors should be considered in interpretation of the changes observed in plasma or urine of the target metabolite(s). Fasting plasma and urine samples from 180 CKD patients and 120 age-matched healthy controls were determined by UPLC-HDMS-metabolomics and quantitative real-time RT-PCR techniques. Compared with healthy controls, patients with CKD showed activation of NF-κB and up-regulation of pro-inflammatory and pro-oxidant mRNA and protein expression as well as down-regulation of Nrf2-associated anti-oxidant gene mRNA and protein expression, accompanied by activated canonical Wnt/β-catenin signaling. 124 plasma and 128 urine metabolites were identified and 40 metabolites were significantly altered in both plasma and urine. Plasma concentration and urine excretion of 25 metabolites were distinctly different between CKD and controls. They were related to amino acid, methylamine, purine and lipid metabolisms. Logistic regression identified four plasma and five urine metabolites. Parts of them were good correlated with eGFR or serum creatinine. 5-Methoxytryptophan and homocystine and citrulline were good correlated with both eGFR and creatinine. Clinical factors were incorporated to establish predictive models. The enhanced metabolite model showed 5-methoxytryptophan, homocystine and citrulline have satisfactory accuracy, sensitivity and specificity for predictive CKD. The dysregulation of CKD was related to amino acid, methylamine, purine and lipid metabolisms. 5-methoxytryptophan, homocystine and citrulline could be considered as additional GFR-associated biomarker candidates and for indicating advanced renal injury. CKD caused dysregulation of the plasma and urine metabolome, activation of inflammatory/oxidative pathway and Wnt/β-catenin signaling and suppression of antioxidant pathway.

Ginger extract protects rat's kidneys against oxidative damage after chronic ethanol administration

Chronic alcohol ingestion is associated with pronounced detrimental effects on the renal system. In the current study, the protective effect of ginger extract on ethanol-induced damage was evaluated through determining 8-OHdG, cystatin C, glomerular filtration rate, and pathological changes such as cell proliferation and fibrosis in rats' kidneys. Male wistar rats were randomly divided into three groups and were treated as follows: (1) control, (2) ethanol and (3) ginger extract treated ethanolic (GETE) groups. After a six weeks period of treatment, the results revealed proliferation of glomerular and tubular cells, fibrosis in glomerular and peritubular and a significant rise in the level of 8-OHdG, cystatin C, plasma urea and creatinine. Moreover, compared to the control group, the ethanol group showed a significant decrease in the urine creatinine and creatinine clearance. In addition, significant amelioration of changes in the structure of kidneys, along with restoration of the biochemical alterations were found in the ginger extract treated ethanolic group, compared to the ethanol group. These findings indicate that ethanol induces kidneys abnormality by oxidative DNA damage and oxidative stress, and that these effects can be alleviated using ginger as an antioxidant and anti-inflammatory agent.

A mouse model of alcoholic liver fibrosis-associated acute kidney injury identifies key molecular pathways

Clinical data strongly indicate that acute kidney injury (AKI) is a critical complication in alcoholic hepatitis, an acute-on-chronic form of liver failure in patients with advanced alcoholic fibrosis. Development of targeted therapies for AKI in this setting is hampered by the lack of an animal model. To enable research into molecular drivers and novel therapies for fibrosis- and alcohol-associated AKI, we aimed to combine carbon tetrachloride (CCl₄)-induced fibrosis with chronic intra-gastric alcohol feeding. Male C57BL/6J mice were administered a low dose of CCl₄ (0.2ml/kg 2× week/6weeks) followed by alcohol intragastrically (up to 25g/kg/day for 3weeks) and with continued CCl₄. We observed that combined treatment with CCl₄ and alcohol resulted in severe liver injury, more pronounced than using each treatment alone. Importantly, severe kidney injury was evident only in the combined treatment group. This mouse model reproduced distinct pathological features consistent with AKI in human alcoholic hepatitis. Transcriptomic analysis of kidneys revealed profound effects in the combined treatment group, with enrichment for damage-associated pathways, such as apoptosis, inflammation, immune-response and hypoxia. Interestingly, Havcr1 and Lcn2, biomarkers of AKI, were markedly up-regulated. Overall, this study established a novel mouse model of fibrosis- and alcohol-associated AKI and identified key mechanistic pathways.

Ethanol Induced Brain Lipid Changes in Mice Assessed by Mass Spectrometry

Alcohol abuse is a chronic disease characterized by the consumption of alcohol at a level that interferes with physical and mental health and causes serious and persistent changes in the brain. Lipid metabolism is of particular interest due to its high concentration in the brain. Lipids are the main component of cell membranes, are involved in cell signaling, signal transduction, and energy storage. In this study, we analyzed lipid composition of chronically ethanol exposed mouse brains. Juvenile (JUV) and adult (ADU) mice were placed on a daily limited-access ethanol intake model for 52 days. After euthanasia, brains were harvested, and total lipids were extracted from brain homogenates. Samples were analyzed using high resolution mass spectrometry and processed by multivariate and univariate statistical analysis. Significant lipid changes were observed in different classes including sphingolipids, fatty acids, lysophosphatidylcholines, and other glycerophospholipids.

Influence of the Alcohol Present in a Phytotherapic Tincture on Male Rat Lipid Profiles and Renal Function

This study evaluated the influence of the alcohol present in a formulation of the antiophidic phytotherapic tincture, Específico-Pessôa, on rat blood biochemical and hematological parameters, and on organ histology. Three groups of rats were treated orally for 10, 15, or 30 days; one group received the tincture, the other received alcohol alone, and the third was a control group. The results of this study indicated that cholesterol levels were significantly increased after 10 days in the alcohol and tincture groups, although these decreased after 30 days in the tincture group. Triglyceride levels were significantly reduced after 15 days in the tincture group and after 30 days in the alcohol and tincture groups. A higher creatinine level was observed in the alcohol and tincture groups after 15 and 30 days. The uric acid levels in these groups were reduced at 10 and 30 days, although this metabolite was elevated at 15 days in the alcohol group. Hydropic multifocal degeneration with lymphohistiocytic infiltration and some polymorphonuclear cells was observed in the livers of rats treated with either the tincture or alcohol. These data demonstrate the importance of considering the potential actions of the alcohol present in pharmaceutical formulations.

Inflammatory PAF Receptor Signaling Initiates Hedgehog Signaling and Kidney Fibrogenesis During Ethanol Consumption

Acute inflammation either resolves or proceeds to fibrotic repair that replaces functional tissue. Pro-fibrotic hedgehog signaling and induction of its Gli transcription factor in pericytes induces fibrosis in kidney, but molecular instructions connecting inflammation to fibrosis are opaque. We show acute kidney inflammation resulting from chronic ingestion of the common xenobiotic ethanol initiates Gli1 transcription and hedgehog synthesis in kidney pericytes, and promotes renal fibrosis. Ethanol ingestion stimulated transcription of TGF-ß, collagens I and IV, and alpha-smooth muscle actin with accumulation of these proteins. This was accompanied by deposition of extracellular fibrils. Ethanol catabolism by CYP2E1 in kidney generates local reactive oxygen species that oxidize cellular phospholipids to phospholipid products that activate the Platelet-activating Factor receptor (PTAFR) for inflammatory phospholipids. Genetically deleting this ptafr locus abolished accumulation of mRNA for TGF-ß, collagen IV, and α-smooth muscle actin. Loss of PTAFR also abolished ethanol-stimulated Sonic (Shh) and Indian hedgehog (Ihh) expression, and abolished transcription and accumulation of Gli1. Shh induced in pericytes and Ihh in tubules escaped to urine of ethanol-fed mice. Neutrophil myeloperoxidase (MPO) is required for ethanol-induced kidney inflammation, and Shh was not present in kidney or urine of mpo^-/- mice. Shh also was present in urine of patients with acute kidney injury, but not in normal individuals or those with fibrotic liver cirrhosis We conclude neither endogenous PTAFR signaling nor CYP2E1-generated radicals alone are sufficient to initiate hedgehog signaling, but instead PTAFR-dependent neutrophil infiltration with myeloperoxidase activation is necessary to initiate ethanol-induced fibrosis in kidney. We also show fibrogenic mediators escape to urine, defining a new class of urinary mechanistic biomarkers of fibrogenesis for an organ not commonly biopsied.

Myeloperoxidase formation of PAF receptor ligands induces PAF receptor-dependent kidney injury during ethanol consumption

Cytochrome P450 2E1 (CYP2E1) induction and oxidative metabolism of ethanol in hepatocytes inflame and damage liver. Chronic ethanol ingestion also induces kidney dysfunction, which is associated with mortality from alcoholic hepatitis. Whether the kidney is directly affected by ethanol or is secondary to liver damage is not established. We found that CYP2E1 was induced in kidney tubules of mice chronically ingesting a modified Lieber-deCarli liquid ethanol diet. Phospholipids of kidney tubules were oxidized and fragmented in ethanol-fed mice with accumulation of azelaoyl phosphatidylcholine (Az-PC), a nonbiosynthetic product formed only by oxidative truncation of polyunsaturated phosphatidylcholine. Az-PC stimulates the inflammatory PAF receptor (PTAFR) abundantly expressed by neutrophils and kidney tubules, and inflammatory cells and myeloperoxidase-containing neutrophils accumulated in the kidneys of ethanol-fed mice after significant hysteresis. Decreased kidney filtration and induction of the acute kidney injury biomarker KIM-1 in tubules temporally correlated with leukocyte infiltration. Genetic ablation of PTAFR reduced accumulation of PTAFR ligands and reduced leukocyte infiltration into kidneys. Loss of this receptor in PTAFR(-/-) mice also suppressed oxidative damage and kidney dysfunction without affecting CYP2E1 induction. Neutrophilic inflammation was responsible for ethanol-induced kidney damage, because loss of neutrophil myeloperoxidase in MPO(-/-) mice was similarly protective. We conclude that ethanol catabolism in renal tubules results in a self-perpetuating cycle of CYP2E1 induction, local PTAFR ligand formation, and neutrophil infiltration and activation that leads to myeloperoxidase-dependent oxidation and damage to kidney function. Hepatocytes do not express PTAFR, so this oxidative cycle is a local response to ethanol catabolism in the kidney.