Effect of garlic-derived organosulfur compounds on mitochondrial function and integrity in isolated mouse liver mitochondria

Induction of Cyp2e1 contributes to asparaginase-induced hepatocyte sensitization to lipotoxicity

One of the leading therapies for acute lymphoblastic leukemia (ALL) is the chemotherapeutic agent PEGylated E. coli-derived-l-asparaginase (PEG-ASNase). Due to the high risk of dose-limiting liver injury, characterized by clinically elevated levels of hepatic transaminases, PEG-ASNase therapy is generally avoided in adult patients. Our preclinical investigations have indicated that PEG-ASNase-induced liver injury is associated with the release of free fatty acids (FFAs) from white adipose tissue (WAT), suggesting potential lipotoxic effects. However, it remains uncertain whether PEG-ASNase directly induces hepatotoxicity or sensitizes hepatocytes to FFA-induced toxicity. Our results show that PEG-ASNase treatment results in hepatocyte apoptosis and lipid peroxidation. Ex vivo and in vitro studies in mouse and human WAT suggest that PEG-ASNase induces the expression of adipose triglyceride lipase (ATGL), activates the lipase, and stimulates adipose tissue lipolysis, suggesting that the FFAs from WAT may contribute to the observed liver injury. Moreover, treatment with PEG-ASNase sensitizes hepatocytes to FFA-induced lipotoxicity. Mechanistically, our RNA-sequencing (RNA-seq) analyses reveal that PEG-ASNase-induced sensitization to lipotoxicity is accompanied by the induction of Cyp2e1. We demonstrated that this sensitization effect is attenuated by both pharmacological and genetic inhibition of Cyp2e1. Our findings suggest that PEG-ASNase therapy induces WAT lipolysis and sensitizes hepatocytes to hepatic lipotoxicity in a Cyp2e1-dependent manner.

Aged garlic therapeutic intervention targeting inflammatory pathways in pathogenesis of bowel disorders

Inflammatory bowel diseases (IBD), which include Crohn's disease and ulcerative colitis, manifest as a result of intricate interactions involving genetic predisposition, environmental factors, intestinal microbiota dynamics, and immune dysregulation, ultimately leading to persistent mucosal inflammation. Addressing this complex pathology requires a nuanced understanding to inform targeted therapeutic strategies. Consequently, our study explored the viability of Aged Garlic Extract (AGE) as an alternative therapeutic regimen for IBD management. Utilizing gas chromatography-mass spectrometry (GC-MS) and scanning electron microscopy (SEM), we characterized AGE, revealing distinctions from Fresh Garlic Extract (FGE), particularly the absence of allicin in AGE and accompanying structural alterations. In In-Vivo experiments employing an IBD rat model, AGE intervention exhibited remarkable antioxidant, antibacterial, and anti-inflammatory properties. Noteworthy outcomes included improved survival rates, mitigation of intestinal damage, restoration of gut microbial diversity, reinforcement of tight junctions, and reversal of mitochondrial dysfunction. Collectively, these effects contributed to the preservation of enterocyte integrity and the attenuation of inflammation. In conclusion, the unique chemical composition of AGE, coupled with its substantial influence on gut microbiota, antioxidant defenses, and inflammatory pathways, positions it as a promising adjunctive therapy for the management of IBD. These observations, synergistically considered with existing research, provide significant insights into the potential utility of AGE in addressing the intricate pathophysiology inherent to IBD. The potential strength of study and rationale of using AGE against IBD includes exploring alternative therapeutic regimens if conventional treatments are associated with side effects, identification of potential hotspots/pathways involved in disease progression and study can provide economically cheaper and naturally occurring alternative to patient community who are struggling to afford expensive medications. These promising findings underscore the necessity for additional investigations to ascertain the feasibility of clinical translation, thereby substantiating the potential therapeutic role of AGE in the management of IBD.

Pesticide-Induced Alterations in Locomotor Activity, Anxiety, and Depression-like Behavior Are Mediated through Oxidative Stress-Related Autophagy: A Persistent Developmental Study in Mice

Chlorpyrifos (CPF), dichlorvos (DDV), and cypermethrin (CP), as commonly used pesticides, have been implicated in inducing neuropsychiatric disorders, such as anxiety, depression-like behaviors, and locomotor activity impairment. However, the exact molecular mechanisms of these adverse effects, particularly in both sexes and their next-generation effects, remain unclear. In this study, we conducted behavioral analysis, along with cellular assays (monodansylcadaverine staining) and molecular investigations (qRT-PCR and western blotting of mTOR, P62, and Beclin-1) to clear the potential role of autophagy in pesticide-induced behavioral alterations. For this purpose, 42 adult female and 21 male inbred ICR mice (F0) were distributed into seven groups. Maternal mice (F0) and 112 F1 offspring were exposed to 0.5 and 1 ppm of CPF, DDV, and CP through drinking water. F1 male and female animals were studied to assess the sex-specific effects of pesticides on brain tissue. Our findings revealed pronounced anxiogenic effects and impaired locomotor activity in mice. F1 males exposed to CPF (1 ppm) exhibited significantly elevated depression-like behaviors compared to other groups. Moreover, pesticide exposure reduced mTOR and P62 levels, while enhancing the Beclin-1 gene and protein expression. These changes in autophagy signaling pathways, coupled with oxidative and neurogenic damage in the cerebral cortex and hippocampus, potentially contribute to heightened locomotor activity, anxiety, and depression-like behaviors following pesticide exposure. This study underscores the substantial impact of pesticides on both physiological and behavioral aspects, emphasizing the necessity for comprehensive assessments and regulatory considerations for pesticide use. Additionally, the identification of sex-specific responses presents a crucial dimension for pharmaceutical sciences, highlighting the need for tailored therapeutic interventions and further research in this field.

Advances of H2S in Regulating Neurodegenerative Diseases by Preserving Mitochondria Function

Neurotoxicity is induced by different toxic substances, including environmental chemicals, drugs, and pathogenic toxins, resulting in oxidative damage and neurodegeneration in mammals. The nervous system is extremely vulnerable to oxidative stress because of its high oxygen demand. Mitochondria are the main source of ATP production in the brain neuron, and oxidative stress-caused mitochondrial dysfunction is implicated in neurodegenerative diseases. H2S was initially identified as a toxic gas; however, more recently, it has been recognized as a neuromodulator as well as a neuroprotectant. Specifically, it modulates mitochondrial activity, and H2S oxidation in mitochondria produces various reactive sulfur species, thus modifying proteins through sulfhydration. This review focused on highlighting the neuron modulation role of H2S in regulating neurodegenerative diseases through anti-oxidative, anti-inflammatory, anti-apoptotic and S-sulfhydration, and emphasized the importance of H2S as a therapeutic molecule for neurological diseases.

A comparative study of smart nanoformulations of diethyldithiocarbamate with Cu4O3 nanoparticles or zinc oxide nanoparticles for efficient eradication of metastatic breast cancer

Metastatic tumor is initiated by metastatic seeds (cancer stem cells "CSCs") in a controlled redox microenvironment. Hence, an effective therapy that disrupts redox balance with eliminating CSCs is critical. Diethyldithiocarbamate (DE) is potent inhibitor of radical detoxifying enzyme (aldehyde dehydrogenase "ALDH"1A) causing effective eradication of CSCs. This DE effect was augmented and more selective by its nanoformulating with green synthesized copper oxide (Cu₄O₃) nanoparticles (NPs) and zinc oxide NPs, forming novel nanocomplexes of CD NPs and ZD NPs, respectively. These nanocomplexes exhibited the highest apoptotic, anti-migration, and ALDH1A inhibition potentials in M.D. Anderson-metastatic breast (MDA-MB) 231 cells. Importantly, these nanocomplexes revealed more selective oxidant activity than fluorouracil by elevating reactive oxygen species with depleting glutathione in only tumor tissues (mammary and liver) using mammary tumor liver metastasis animal model. Due to higher tumoral uptake and stronger oxidant activity of CD NPs than ZD NPs, CD NPs had more potential to induce apoptosis, suppress hypoxia-inducing factor gene, and eliminate CD44⁺CSCs with downregulating their stemness, chemoresistance, and metastatic genes and diminishing hepatic tumor marker (α-fetoprotein). These potentials interpreted the highest tumor size reduction with complete eradicating tumor metastasis to liver in CD NPs. Consequently, CD nanocomplex revealed the highest therapeutic potential representing a safe and promising nanomedicine against the metastatic stage of breast cancer.

Diallyl trisulfide plays an antifibrotic role by inhibiting the expression of Bcl‐2 in hepatic stellate cells

Hepatic fibrosis is an important early stage in the evolution of liver cirrhosis, and specific medicine and therapeutic measures are unavailable to date. Hepatic stellate cells (HSCs) are the main cells involved in the formation of hepatic fibrosis, and induction of the apoptosis of HSCs is an important strategy for the treatment of hepatic fibrosis. Diallyl trisulfide (DATS) is a natural product and is the main active ingredient in garlic. However, the exact molecular mechanisms underlying HSC apoptosis induced by DATS are not well understood. This study aimed to analyze the efficiency and mechanism of DATS in hepatic fibrosis. Different concentrations (25, 50, 100, and 200 μM) of DATS were used to treat HSCs. Changes in cell morphology and formation of apoptotic bodies were observed under an inverted microscope and an electric microscope. Bcl‐2 signaling involving Bax, Caspase‐3, Caspase‐6, Caspase‐8, Caspase‐9, p53, Apaf‐1, and Cyto‐c in fibrosis were examined, which is a critical step in the evaluation of antihepatic fibrosis agents. We also evaluated the effect of DATS on the cellular morphology of HSCs and apoptosis‐related factors under different Bcl‐2 expression states. Our results suggest that DATS regulates hepatic fibrosis by blocking the Bcl‐2 signaling pathway and upregulating the Bax/Bcl‐2 ratio.

The crucial role of oxidative stress in non-alcoholic fatty liver disease-induced male reproductive toxicity: the ameliorative effects of Iranian indigenous probiotics

Several studies have focused on the high potential effects of probiotics on the reproductive system. However, there is a paucity of information regarding the ameliorative intracellular roles of indigenous Iranian yogurt-extracted/cultured probiotics on animals' reproductive health suffering from obesity and/or fatty liver disease, such as non-alcoholic fatty liver disease (NAFLD). For this purpose, simultaneously with the consumption of D-fructose (200 g/1000 mL water, induction of NAFLD model), all pubertal animals were also gavaged every day for 63 consecutive days with extracted probiotics, including 1 × 109 CFU/mL of Lactobacillus acidophilus (LA), Bifidobacterium spp. (BIF), Bacillus coagulans (BC), Lactobacillus rhamnosus (LR), and a mixture form (LA + BIF + BC + LR). At the end of the ninth week, the indices of epididymal sperm, and oxidative stress, as well as histopathological changes, were assessed. The results show that NAFLD could induce robust oxidative stress, highlighted as considerable increments in ROS level, TBARS content, total oxidized protein levels, along with severe decrements in reduced glutathione reservoirs, total antioxidant capacity in the hepatic and testicular tissues, as well as testicular and hepatic histopathological alterations. Moreover, a significant decrease in the percentage of sperm progressive motility, sperm count, and membrane integrity along with an increment in the percentage of sperm abnormality was detected in NAFLD animals. The observed adverse effects were significantly reversed upon probiotics treatment, especially in the group challenged with a mixture of all probiotics. Taken together, these findings indicate that the indigenous yogurt-isolated/cultured probiotics had a high potential antioxidant activity and the ameliorative effect against reprotoxicity and blood biochemical alterations induced by the NAFLD model. Highlights: 1. Reproductive indices could be reversely affected by xenobiotics and diseases. 2. NAFLD and cholestasis considerably affect the reproductive system in both genders. 3. NAFLD induced hepatic and testicular oxidative stress (OS). 4. NAFLD induced histopathological alterations and spermatotoxicity through OS. 5. The adverse effects were significantly reversed upon exposure to probiotics.

Mitochondrial dysfunction and oxidative stress are involved in the mechanism of tramadol-induced renal injury

Tramadol (TMDL) is an opioid analgesic widely administered for the management of moderate to severe pain. On the other hand, TMDL is commonly abused in many countries because of its availability and cheap cost. Renal injury is related to high dose or chronic administration of TMDL. No precise mechanism for TMDL-induced renal damage has been identified so far. The current study aimed to evaluate the potential role of oxidative stress and mitochondrial impairment in the pathogenesis of TMDL-induced renal injury. For this purpose, rats were treated with TMDL (40 and 80 ​mg/kg, i.p, 28 consecutive days). A significant increase in serum Cr and BUN was detected in TMDL groups. On the other hand, TMDL (80 ​mg/kg) caused a substantial increase in urine glucose, ALP, protein, and γ-GT levels. Moreover, urine Cr was significantly decreased in TMDL-treated rats (40 and 80 ​mg/kg). Renal histopathological alterations included inflammation, necrosis, and tubular degeneration in the kidney of TMDL-treated animals. Reactive oxygen species (ROS) formation, increased oxidized glutathione (GSSG), lipid peroxidation, and protein carbonylation was increased, whereas total antioxidant capacity and reduced glutathione levels were considerably decreased in TMDL groups. Significant mitochondrial impairment was also detected in the form of mitochondrial depolarization, adenosine-tri-phosphate (ATP) depletion, mitochondrial permeabilization, lipid peroxidation, and decreased mitochondrial dehydrogenase activity in the kidney of TMDL (80 ​mg/kg)-treated animals. These data suggest mitochondrial impairment and oxidative stress as mechanisms involved in the pathogenesis of TMDL-induced renal injury.

Metformin alleviates cholestasis-associated nephropathy through regulating oxidative stress and mitochondrial function

Background and aim

Cholestasis-associated renal injury or cholemic nephropathy (CN) is a serious clinical problem. Previous studies mentioned that oxidative stress and mitochondrial impairment play a role in CN. There is no specific pharmacological intervention for CN. Metformin is an anti-diabetic drug administered for decades. On the other hand, novel pharmacological properties have emerged for this drug. The effect of metformin on oxidative stress parameters has been well-recognized in different experimental models. It has also been found that metformin positively affected mitochondrial function. The current study aimed to evaluate the effects of metformin in an animal model of CN.

Methods

Rats underwent bile duct ligation (BDL) and were treated with metformin (250 and 500 mg/kg) for 14 consecutive days. Two weeks after the BDL operations, urine, serum, and kidney samples were collected and analyzed.

Results

Markers of oxidative stress, including reactive oxygen species (ROS) formation, lipid peroxidation, protein carbonylation, depleted antioxidant capacity, and decreased glutathione (GSH) levels were detected in BDL animals. Moreover, mitochondrial indices, including adenosine triphosphate (ATP) level, dehydrogenase activity, mitochondrial membrane potential, and mitochondrial permeability, were impaired in the kidney of cholestatic rats. Renal histopathological alterations in cholestatic animals included tubular degeneration and interstitial inflammation, cast formation, and fibrosis. It was found that metformin significantly alleviated oxidative stress and improved mitochondrial indices in the kidney of cholestatic rats. Tissue histopathological alterations were also mitigated in metformin-treated groups.

Conclusions

Metformin could be a candidate for managing CN. The nephroprotective role of metformin is primarily associated with its effects on oxidative stress parameters and mitochondrial function.

Silymarin mitigates bile duct obstruction-induced cholemic nephropathy

Bile duct obstruction or cholestasis can occur by several diseases or xenobiotics. Cholestasis and the accumulation of the bile constituents in the liver primarily damage this organ. On the other hand, extrahepatic organs are also affected by cholestasis. The kidney is the most affected tissue during cholestatic liver injury. Cholestasis-associated renal injury is known as cholemic nephropathy (CN). Several lines of evidence specify the involvement of oxidative stress and mitochondrial impairment in the pathogenesis of CN. The current study aimed to assess the role of silymarin as a potent antioxidant on CN-induced oxidative stress and mitochondrial dysfunction in the kidney. Bile duct ligated (BDL) rats were treated with silymarin (10 and 100 mg/kg, oral) for seven consecutive days. A significant increase in reactive oxygen species (ROS), lipid peroxidation, protein carbonylation, and oxidized glutathione (GSSG) levels were evident in the kidney of BDL animals. Moreover, reduced glutathione (GSH) content and total antioxidant capacity were significantly decreased in the kidney of cholestatic rats. Mitochondrial depolarization, decreased mitochondrial dehydrogenases activity, mitochondrial permeabilization, and depleted ATP stores were detected in the kidney mitochondria isolated from BDL animals. Kidney histopathological alterations, as well as serum and urine levels of renal injury biomarkers, were also significantly different in the BDL group. It was found that silymarin treatment significantly ameliorated CN-induced renal injury. The antioxidant effects of silymarin and its positive impact on mitochondrial indices seem to play a significant role in its renoprotective effects during cholestasis.

In Vitro and In Vivo Evidence on the Role of Mitochondrial Impairment as a Mechanism of Lithium-Induced Nephrotoxicity

Lithium is abundantly administered against bipolar disorder. On the other hand, the lithium-induced renal injury is a clinical complication which commonly reveals as drug-induced diabetes insipidus. However, lithium-induced cytotoxicity might also play a role in the adverse effects of this drug on the kidney. There is no clear cellular and molecular mechanism(s) for lithium-induced nephrotoxicity. The current study was designed to assess the effect of lithium on kidney tissue oxidative stress biomarkers and mitochondrial function and its relevance to drug-induced nephrotoxicity and electrolyte imbalance. Rats were treated with lithium (lithium carbonate, 25 and 50 mg/kg/day, i.p., for 28 consecutive days). Kidney mitochondria were also isolated from rats and exposed to increasing concentrations of lithium (0.01-10 mM). Serum and urine biomarkers of kidney injury, kidney tissue markers of oxidative stress, and renal histopathological changes were assessed. Moreover, several mitochondrial indices were monitored. Lithium-induced renal injury revealed a significant increase in urine and serum biomarkers of renal impairment. Lithium caused an increase in the kidney reactive oxygen species (ROS) level and lipid peroxidation (LPO). Renal glutathione (GSH) reservoirs were also depleted, and tissue antioxidant capacity decreased in lithium-treated animals. Significant tissue histopathological changes, including necrosis, Bowman capsule dilation, and interstitial inflammation, were evident in lithium-treated animals. On the other hand, significant alterations in kidney mitochondrial function were detected in lithium-treated groups. These data mention oxidative stress, mitochondrial dysfunction, and cellular energy crisis as the potential primary mechanisms for lithium-induced renal injury.

The Role of Mitochondrial Impairment and Oxidative Stress in the Pathogenesis of Lithium-Induced Reproductive Toxicity in Male Mice

Lithium (Li+) is prescribed against a wide range of neurological disorders. Besides its excellent therapeutic properties, there are several adverse effects associated with Li+. The impact of Li+ on renal function and diabetes insipidus is the most common adverse effect of this drug. On the other hand, infertility and decreased libido is another complication associated with Li+. It has been found that sperm indices of functionality, as well as libido, is significantly reduced in Li+-treated men. These adverse effects might lead to drug incompliance and the cessation of drug therapy. Hence, the main aims of the current study were to illustrate the mechanisms of adverse effects of Li+ on the testis tissue, spermatogenesis process, and hormonal changes in two experimental models. In the in vitro experiments, Leydig cells (LCs) were isolated from healthy mice, cultured, and exposed to increasing concentrations of Li+ (0, 10, 50, and 100 ppm). In the in vivo section of the current study, mice were treated with Li+ (0, 10, 50, and 100 ppm, in drinking water) for five consecutive weeks. Testis and sperm samples were collected and assessed. A significant sign of cytotoxicity (LDH release and MTT assay), along with disrupted testosterone biosynthesis, impaired mitochondrial indices (ATP level and mitochondrial depolarization), and increased biomarkers of oxidative stress were detected in LCs exposed to Li+. On the other hand, a significant increase in serum and testis Li+ levels were detected in drug-treated mice. Moreover, ROS formation, LPO, protein carbonylation, and increased oxidized glutathione (GSSG) were detected in both testis tissue and sperm specimens of Li+-treated mice. Several sperm anomalies were also detected in Li+-treated animals. On the other hand, sperm mitochondrial indices (mitochondrial dehydrogenases activity and ATP levels) were significantly decreased in drug-treated groups where mitochondrial depolarization was increased dose-dependently. Altogether, these data mention oxidative stress and mitochondrial impairment as pivotal mechanisms involved in Li+-induced reproductive toxicity. Therefore, based on our previous publications in this area, therapeutic options, including compounds with high antioxidant properties that target these points might find a clinical value in ameliorating Li+-induced adverse effects on the male reproductive system.

Taurine mitigates bile duct obstruction-associated cholemic nephropathy: effect on oxidative stress and mitochondrial parameters

AIM OF THE STUDY

Cholestasis is a serious complication affecting other organs such as the liver and kidney. Oxidative stress and mitochondrial impairment are proposed as the primary mechanisms for cholestasis-induced organ injury. Taurine (TAU) is the most abundant free amino acid in the human body, which is not incorporated in the structure of proteins. Several pharmacological effects have been attributed to TAU. It has been reported that TAU effectively mitigated oxidative stress and modulated mitochondrial function. The current study aimed to evaluate the impact of TAU on oxidative stress biomarkers and mitochondrial parameters in the kidney of cholestatic animals.

MATERIAL AND METHODS

Bile duct ligated (BDL) rats were used as an antioxidant model of cholestasis. Animals were treated with TAU (500 and 1000 mg/kg, oral) for seven consecutive days. Animals were anesthetized (thiopental 80 mg/kg, i.p.), and kidney and blood specimens were collected.

RESULTS

Severe elevation in serum and urine biomarkers of renal injury was evident in the BDL group. Significant lipid peroxidation, reactive oxygen species (ROS) formation, and protein carbonylation were detected in the kidney of BDL animals. Furthermore, depleted glutathione reservoirs and a significant decrease in the antioxidant capacity of renal tissue were detected in cholestatic rats. Renal tubular atrophy and interstitial inflammation were evident in BDL animals. Cholestasis also caused significant mitochondrial dysfunction in the kidney. TAU significantly prevented cholestasis-induced renal injury by inhibiting oxidative stress and mitochondrial impairment.

CONCLUSIONS

These data indicate TAU as a potential therapeutic agent in the management of cholestasis-induced renal injury.

Intranasal insulin improves mitochondrial function and attenuates motor deficits in a rat 6-OHDA model of Parkinson's disease

Aims

Experimental and clinical evidences demonstrate that common dysregulated pathways are involved in Parkinson’s disease (PD) and type 2 diabetes. Recently, insulin treatment through intranasal (IN) approach has gained attention in PD, although the underlying mechanism of its potential therapeutic effects is still unclear. In this study, we investigated the effects of insulin treatment in a rat model of PD with emphasis on mitochondrial function indices in striatum.

Methods

Rats were treated with a daily low dose (4IU/day) of IN insulin, starting 72 h after 6‐OHDA‐induced lesion and continued for 14 days. Motor performance, dopaminergic cell survival, mitochondrial dehydrogenases activity, mitochondrial swelling, mitochondria permeability transition pore (mPTP), mitochondrial membrane potential (Δψ_m), reactive oxygen species (ROS) formation, and glutathione (GSH) content in mitochondria, mitochondrial adenosine triphosphate (ATP), and the gene expression of PGC‐1α, TFAM, Drp‐1, GFAP, and Iba‐1 were assessed.

Results

Intranasal insulin significantly reduces 6‐OHDA‐induced motor dysfunction and dopaminergic cell death. In parallel, it improves mitochondrial function indices and modulates mitochondria biogenesis and fission as well as activation of astrocytes and microglia.

Conclusion

Considering the prominent role of mitochondrial dysfunction in PD pathology, IN insulin as a disease‐modifying therapy for PD should be considered for extensive research.

Epigallocatechin gallate and coenzyme Q10 attenuate cisplatin-induced hepatotoxicity in rats via targeting mitochondrial stress and apoptosis

Despite the extensive use of cisplatin (CP) as a chemotherapeutic agent, its clinical use is often restricted by undesirable side effects, such as toxicity to normal tissues. The aim of this study was to probe the effect of a combinatorial treatment of low multiple doses of antioxidants on CP-induced toxicity and the mitochondrial apoptotic pathway in hepatocytes. Animals received a single toxic dose of CP (7.5 mg/kg body weight) with or without combined multiple doses of epigallocatechin gallate (EGCG) and coenzyme Q10 (CoQ10) (15 and 5 mg/kg body weight, respectively). CP-treated animals showed altered biochemical parameters, denoting hepatotoxicity, which was markedly improved by the multidose treatment with EGCG + CoQ10. The increased levels of oxidants found in the cytosolic and mitochondrial fractions isolated from the liver of CP-administered rats were significantly attenuated by the combinatorial doses of antioxidants. EGCG + CoQ10 ameliorated the CP-induced compromised antioxidant defenses, oxidative modification of macromolecules, decreased activities of respiratory chain enzymes, altered membrane depolarization, and swelling of liver mitochondria. Furthermore, EGCG + CoQ10 treatment inhibited CP-induced apoptosis by suppressing the activation and mitochondrial accumulation of proapoptotic proteins and preventing the inhibition of antiapoptotic protein expression, cytochrome c efflux, caspase-3 activation, and DNA fragmentation. Histological findings further confirmed the protective effects of EGCG + CoQ10 against CP-induced cellular injury. Our findings revealed that the combination of EGCG and CoQ10, owing to their individual antioxidant properties, can be an effective remedy, which by maintaining redox hemostasis attenuate the mitochondrial stress-mediated molecular and cellular processes involved in CP-induced liver toxicity and cell death.

Spermatotoxic Effects of Single-Walled and Multi-Walled Carbon Nanotubes on Male Mice

Carbon-based nanomaterials possess a remarkably high potential for biomedical applications due to their physical properties; however, their detrimental effects on reproduction are also concerned. Several reports indicate the toxicity of carbon nanotubes (CNT); nevertheless, their impact on intracellular organelles in the male reproductive organs has not been fully elucidated. Herein, we report on the reprotoxicity of single-walled (SWCNT) and multi-walled carbon nanotubes (MWCN) on several intracellular events and histological criteria in pubertal male BALB/c mice orally treated with 0, 10, and 50 mg/kg/day doses for 5 weeks. Biomarkers of oxidative stress and mitochondrial functionality, histopathological alterations, and epididymal sperm characteristics were determined. Oral administration of CNTs at 10 and 50 mg/kg evoked a significant decrement in weight coefficient, sperm viability and motility, hypo-osmotic swelling (HOS) test, sperm count, mitochondrial dehydrogenase activity, ATP content, total antioxidant capacity, and GSH/GSSH ratio in the testis and epididymal spermatozoa. On the other hand, percent abnormal sperm, testicular and sperm TBARS contents, protein carbonylation, ROS formation, oxidized glutathione level, and sperm mitochondrial depolarization were considerably increased. Significant histopathological and stereological alterations in the testis occurred in the groups challenged with CNTs. The current findings indicated that oxidative stress and mitochondrial impairment might substantially impact CNTs-induced reproductive system injury and sperm toxicity. The results can also be used to establish environmental standards for CNT consumption by mammals, produce new chemicals for controlling the rodent populations, and develop therapeutic approaches against CNTs-associated reproductive anomalies in the males exposed daily to these nanoparticles.

The mechanisms of arsenic-induced ovotoxicity, ultrastructural alterations, and autophagic related paths: An enduring developmental study in folliculogenesis of mice

Arsenic (As) exerts a wide range of adverse effects on biological systems, including the reproductive organs in males and females. However, the mechanisms of As-induced reproductive toxicity are mostly obscure. Recently, we showed that autophagy is an essential route for As₂O₃-induced reprotoxicity through the hypothalamic-pituitary-gonadal-sperm (HPG-S) axis in pubertal and matured F1-male mice. However, the role of autophagy in As₂O₃- induced ovarian toxicity is mostly unknown. Hence, this study aimed to elucidate the role of oxidative stress, mitochondrial impairment, and autophagic processes in the ovary of As-exposed female mice. For this purpose, mature female mice were challenged with 0, low (0.2), medium (2), and high (20 ppm) As₂O₃ from 35-days before mating till weaning their pups, and the F1- females from weaning until maturity. Then, all the mice were sacrificed, and oxidative stress parameters, mitochondrial indices, electron microscopic evaluation of the ovaries, expression of autophagic-related genes and proteins, and autophagosome formation were assessed. It was shown that medium and high As₂O₃ doses were a potent inducer of oxidative stress, mitochondrial dysfunction, and autophagy in the ovary of F1-generation. A dose-dependent increment in the gene expression of PDK₁, PI3K, TSC2, AMPK, ULK1, ATG13, Beclin1, ATG12, ATG5, LC3, P62, ATG3, ATG7, and p62, as well as protein expression of Beclin1, and LC3- I, II, was evident in the ovaries of the As-treated animals. Moreover, a dose-dependent decrease in the expression of mTOR and Bcl-2 genes, and mTOR protein was detected with increasing doses of As, suggesting that As treatment-induced autophagy. Along with a dose-dependent increase in the number of MDC-labeled autophagic vacuoles, transmission electron microscopy also confirmed more autophagosomes and injured mitochondria in medium and high As₂O₃ doses groups. As₂O₃ also negatively affected the mean body weight, litter size, organ coefficient, and stereological indices in female mice. Finally, in physiological conditions, arsenic trioxide (As₂O₃) leads to an increased level of autophagy in the oocyte when many oocytes were being lost. These findings indicated that an imbalance in the oxidant-antioxidant system, mitochondrial impairment, and the autophagic process, through inhibition of mTOR, dependent and independent pathways, and Bcl-2, as well as activation of AMPK/PI3K/Beclin1/LC3 routes, could play a pivotal role in As-induced reproductive toxicity through ovarian dysfunction in females.

Taurine mitigates cirrhosis-associated heart injury through mitochondrial-dependent and antioxidative mechanisms

Cirrhosis-induced heart injury and cardiomyopathy is a serious consequence of this disease. It has been shown that bile duct ligated (BDL) animals could serve as an appropriate experimental model to investigate heart tissue injury in cirrhosis. The accumulation of cytotoxic chemicals (e.g., bile acids) could also adversely affect the heart tissue. Oxidative stress and mitochondrial impairment are the most prominent mechanisms of bile acid cytotoxicity. Taurine (Tau) is the most abundant non-protein amino acid in the human body. The cardioprotective effects of this amino acid have repeatedly been investigated. In the current study, it was examined whether mitochondrial dysfunction and oxidative stress are involved in the pathogenesis of cirrhosis-induced heart injury. Rats underwent BDL surgery. BDL animals received Tau (50, 100, and 500 mg/kg, i.p.) for 42 consecutive days. A significant increase in oxidative stress biomarkers was detected in the heart tissue of BDL animals. Moreover, it was found that heart tissue mitochondrial indices of functionality were deteriorated in the BDL group. Tau treatment significantly decreased oxidative stress and improved mitochondrial function in the heart tissue of cirrhotic animals. These data provide clues for the involvement of mitochondrial impairment and oxidative stress in the pathogenesis of heart injury in BDL rats. On the other hand, Tau supplementation could serve as an effective ancillary treatment against BDL-associated heart injury. Mitochondrial regulating and antioxidative properties of Tau might play a fundamental role in its mechanism of protective effects in the heart tissue of BDL animals.

Arsenic-induced autophagic alterations and mitochondrial impairments in HPG-S axis of mature male mice offspring (F1-generation): A persistent toxicity study

Arsenic (As) has been implicated in causing reproductive toxicity, but the precise cellular pathway through which the As toxicity in mature F1- male mice hypothalamic-pituitary- gonadal- sperm (HPG-S) axis is induced has not well been documented. Hence, parental mice were treated to As2O3 (0, 0.2, 2, and 20 ppm in deionized water) from five weeks before mating until weaning, and the male pups from weaning to maturity. Afterward, the markers of oxidative stress, mitochondrial impairment, and autophagy as fundamental mechanisms of cytotoxicity and organ injury were evaluated. Higher As2O3 doses (2 and 20 ppm) were a potent inducer of oxidative stress, mitochondrial dysfunction, and autophagy in HPG-S axis. Concomitant with a dose-dependent increase in the number of MDC-labeled autophagic vacuoles in the HPG axis, an adverse dose-dependent effect was observed on the mean body weight, litter size, organ coefficient, and spermatogenesis. Transmission electron microscopy also revealed more autophagosomes at high As2O3 dosage. Concomitant with a dose-dependent increment in gene expression of PI3K, Atg5, Atg12, as well as protein expression of Beclin1, LC3- I, II, P62 in HPG axis tissues and Atg12 in the pituitary; a dose-dependent decrease in mTOR gene expression was recorded in the HPG tissues of mature F1-males. These observations provide direct evidence that oxidative stress-induced mitochondrial impairments and autophagic cell death, through AMPK/TSC/mTOR and LC3 related pathways, are fundamental mechanisms for As2O3- induced toxicity on the reproductive system in mature male mice offspring.

N-acetyl cysteine treatment preserves mitochondrial indices of functionality in the brain of hyperammonemic mice

AIM OF THE STUDY

Acute or chronic live failure could result in hyperammonemia and hepatic encephalopathy (HE). HE is a clinical complication characterized by severe cognitive dysfunction and coma. The ammonium ion (NH4 +) is the most suspected toxic molecule involved in the pathogenesis of HE. NH4 + is a neurotoxic agent. Different mechanisms, including oxidative/nitrosative stress, inflammatory response, excitotoxicity, and mitochondrial impairment, are proposed for NH4 +-induced neurotoxicity. N-acetyl cysteine (NAC) is a well-known thiol-reductant and antioxidant agent. Several investigations also mentioned the positive effects of NAC on mitochondrial function. In the current study, the effect of NAC treatment on brain mitochondrial indices and energy status was investigated in an animal model of HE.

MATERIAL AND METHODS

Acetaminophen (APAP)-induced acute liver failure was induced by a single dose of the drug (800 mg/kg, i.p.) to C57BL/6J mice. Plasma and brain levels of NH4 + were measured. Then, brain mitochondria were isolated, and several indices, including mitochondrial depolarization, ATP level, lipid peroxidation, glutathione content, mitochondrial permeabilization, and dehydrogenase activity, were assessed.

RESULTS

A significant increase in plasma and brain NH4 + was evident in APAP-treated animals. Moreover, mitochondrial indices of functionality were impaired, and mitochondrial oxidative stress biomarkers were significantly increased in APAP-treated mice. It was found that NAC treatment (100, 200, and 400 mg/kg, i.p.) significantly mitigated mitochondrial impairment in the brain of APAP-treated animals.

CONCLUSIONS

These data suggest the effects of NAC on brain mitochondrial function and energy status as a pivotal mechanism involved in its neuroprotective properties during HE.

Suppression of cirrhosis-related renal injury by N-acetyl cysteine

Cirrhosis-induced renal injury or cholemic nephropathy (CN) is a serious clinical complication with poor prognosis. CN could finally lead to renal failure and the need for organ transplantation. Unfortunately, there is no specific pharmacological intervention against CN to date. On the other hand, various studies mentioned the role of oxidative stress and mitochondrial impairment in the pathogenesis of CN. The current study aimed to evaluate the potential protective effects of NAC as a thiol-reducing agent and antioxidant in CN. Bile duct ligation (BDL) was used as a reliable animal model of cholestasis. BDL animals received NAC (0.25% and 1% w: v) in drinking water for 28 consecutive days. Finally, urine, blood, and kidney samples were collected and analyzed. Significant elevation in serum biomarkers of renal injury, along with urine markers of kidney damage, was evident in the BDL group. Moreover, markers of oxidative stress, including reactive oxygen species (ROS) formation, lipid peroxidation, protein carbonylation, and increased oxidized glutathione (GSSG) were evident detected in the kidney of cholestatic rats. Renal tissue antioxidant capacity and reduced glutathione (GSH) were also significantly depleted in the BDL group. Significant mitochondrial depolarization, depleted ATP content, and mitochondrial permeabilization was also detected in mitochondria isolated from the kidney of cholestatic animals. Renal histopathological alterations consisted of significant tissue fibrosis, interstitial inflammation, and tubular atrophy. It was found that NAC (0.25 and 1% in drinking water for 28 consecutive days) blunted histopathological changes, decreased markers of oxidative stress, and improved mitochondrial indices in the kidney of cirrhotic rats. Moreover, serum and urine biomarkers of renal injury were also mitigated in upon NAC treatment. These data indicate a potential renoprotective role for NAC in cholestasis. The effects of NAC on cellular redox state and mitochondrial function seem to play a fundamental role in its renoprotective effects during CN.

Short chain fatty acids may improve hepatic mitochondrial energy efficiency in heat stressed-broilers

The present study was conducted to investigate the effects of four dietary fat types and two environmental temperatures on the hepatic mitochondrial energetic in male broilers exposed to heat stress. The birds were kept in two separate rooms at 24 °C or 36 °C from 32 to 42 d of age with four experimental groups in each room. The birds fed on the diets supplemented containing rich sources of long-chain saturated fatty acids (beef tallow), middle-length-chain saturated FA (coconut oil), monounsaturated FA (olive oil), or polyunsaturated FA (soybean oil) for ten days. At 36 °C, the highest body weight and lowest feed conversion ratio were recorded in the birds fed on the diets supplemented with coconut oil or beef tallow. Temperature and fat type significantly affected the activities of the mitochondrial electron transport chain complexes (P < 0.01). There was a significant interaction between the temperature and fat type (P < 0.01). Generally, electron transport chain complexes I-V enzymatic activities were decreased at 36 °C. The coconut oil-fed birds showed the highest complex I activity at both temperatures. The beef tallow-fed broilers showed the lowest complex II activity at 24 °C. In birds exposed to 36 °C, complex II activity was higher for birds fed saturated coconut oil or beef tallow than those feeding the unsaturated olive oil or soybean oil-supplemented diets. At 24 °C, the highest and lowest complex III activities were recorded for the coconut oil- and beef tallow-supplemented diets, respectively. At 36 °C, the activity of complex III was coconut oil > beef tallow > olive oil > soybean oil. At 24 °C, complex IV activity was highest in coconut oil- or soybean oil-fed broilers; and at 36 °C, complex IV showed the lowest activity in soybean oil-fed birds. The highest complex IV activity was observed in coconut oil-fed chickens followed by olive oil-fed and beef tallow-fed birds, respectively. At 24 or 36 °C, the highest and lowest complex V activity was observed in coconut oil-fed and soybean oil-fed chickens, respectively. ATP concentration and mitochondrial membrane potential were in the order of coconut oil > beef tallow > olive oil > soybean oil at both temperatures. Temperature and fat type significantly affected the avANT mRNA concentration. Exposure of broilers to 36 °C generally decreased the mRNA expression of avANT, with beef tallow- or coconut oil-supplemented birds showing a lower avANT mRNA expression than those receiving olive oil- or soybean oil-supplemented diets. These findings provide further information on the use of fat sources in the diet of heat stressed-broilers.

Taurine Treatment Provides Neuroprotection in a Mouse Model of Manganism

Manganese (Mn) is a trace element involved in many physiological processes. However, excessive Mn exposure leads to neurological complications. Although no precise mechanism(s) has been found for Mn-induced neurotoxicity, oxidative stress and mitochondrial injury seem to play a relevant role in this complication. On the other hand, there is no protective strategy against Mn neurotoxicity so far. Taurine is an amino acid with significant neuroprotective properties. The current study was designed to evaluate the effect of taurine supplementation and its potential mechanism(s) of action in a mouse model of manganism. Animals were treated with Mn (100 mg/kg, s.c) alone and/or in combination with taurine (50, 100, and 500 mg/kg, i.p, for eight consecutive days). Severe locomotor dysfunction along with a significant elevation in brain tissue biomarkers of oxidative stress was evident in Mn-exposed mice. On the other hand, it was revealed that mitochondrial indices of functionality were hampered in Mn-treated animals. Taurine supplementation (50, 100, and 500 mg/kg, i.p) alleviated Mn-induced locomotor deficit. Moreover, this amino acid mitigated oxidative stress biomarkers and preserved brain tissue mitochondrial indices of functionality. These data introduce taurine as a potential neuroprotective agent against Mn neurotoxicity. Antioxidative and mitochondria protecting effects of taurine might play a fundamental role in its neuroprotective properties against Mn toxicity.

The potential role of mitochondrial impairment in the pathogenesis of imatinib-induced renal injury

Imatinib is a tyrosine kinase inhibitor widely administered against chronic myeloid leukemia. On the other hand, drug-induced kidney proximal tubular injury, electrolytes disturbances, and renal failure is a clinical complication associated with imatinib therapy. There is no precise cellular mechanism(s) for imatinib-induced renal injury. The current investigation aimed to evaluate the role of mitochondrial dysfunction and oxidative stress in the pathogenesis of imatinib nephrotoxicity. Rats received imatinib (50 and 100 mg/kg, oral, 14 consecutive days). Serum and urine biomarkers of renal injury and markers of oxidative stress in the kidney tissue were assessed. Moreover, kidney mitochondria were isolated, and mitochondrial indices, including mitochondrial depolarization, dehydrogenases activity, mitochondrial permeabilization, lipid peroxidation (LPO), mitochondrial glutathione levels, and ATP content were determined. A significant increase in serum (Creatinine; Cr and blood urea nitrogen; BUN) and urine (Glucose, protein, gamma-glutamyl transferase; γ-GT, and alkaline phosphatase; ALP) biomarkers of renal injury, as well as serum electrolytes disturbances (hypokalemia and hypophosphatemia), were evident in imatinib-treated animals. On the other hand, imatinib (100 mg/kg) caused an increase in kidney ROS and LPO. Renal tubular interstitial nephritis, tissue necrosis, and atrophy were evident as tissue histopathological changes in imatinib-treated rats. Mitochondrial parameters were also adversely affected by imatinib administration. These data represent mitochondrial impairment, renal tissue energy crisis, and oxidative stress as possible mechanisms involved in the pathogenesis of imatinib-induced renal injury and serum electrolytes disturbances.

Carnosine Mitigates Manganese Mitotoxicity in an In Vitro Model of Isolated Brain Mitochondria

Purpose: Manganese (Mn) is a neurotoxic chemical which induces a wide range of complications in the brain tissue. Impaired locomotor activity and cognitive dysfunction are associated with high brain Mn content. At the cellular level, mitochondria are potential targets for Mn toxicity. Carnosine is a dipeptide abundantly found in human brain. Several pharmacological properties including mitochondrial protecting and antioxidative effects have been attributed to carnosine. The current study aimed to evaluate the effect of carnosine treatment on Mn-induced mitochondrial dysfunction in isolated brain mitochondria. Methods: Mice brain mitochondria were isolated based on the differential centrifugation method and exposed to increasing concentrations of Mn (10 µM-10 mM). Carnosine (1 mM) was added as the protective agent. Mitochondrial indices including mitochondrial depolarization, reactive oxygen species (ROS) formation, mitochondrial dehydrogenases activity, ATP content, and mitochondrial swelling and permeabilization were assessed. Results: Significant deterioration in mitochondrial indices were evident in Mn-exposed brain mitochondria. On the other hand, it was found that carnosine (1 mM) treatment efficiently prevented Mn-induced mitochondrial impairment. Conclusion: These data propose mitochondrial protection as a fundamental mechanism for the effects of carnosine against Mn toxicity. Hence, this peptide might be applicable against Mn neurotoxicity with different etiologies (e.g., in cirrhotic patients).

Ammonia-induced mitochondrial impairment is intensified by manganese co-exposure: relevance to the management of subclinical hepatic encephalopathy and cirrhosis-associated brain injury

Aim of the study

Hepatic encephalopathy (HE) is a neuropsychiatric syndrome ensuing from liver failure. The liver is the major site of ammonia detoxification in the human body. Hence, acute and chronic liver dysfunction can lead to hyperammonemia. Manganese (Mn) is a trace element incorporated in several physiological processes in the human body. Mn is excreted through bile. It has been found that cirrhosis is associated with hyperammonemia as well as body Mn accumulation. The brain is the primary target organ for both ammonia and Mn toxicity. On the other hand, brain mitochondria impairment is involved in the mechanism of Mn and ammonia neurotoxicity.

Material and methods

The current study was designed to evaluate the effect of Mn and ammonia and their combination on mitochondrial indices of functionality in isolated brain mitochondria. Isolated brain mitochondria were exposed to increasing concentrations of ammonia and Mn alone and/or in combination and several mitochondrial indices were assessed.

Results

The collapse of mitochondrial membrane potential, increased mitochondrial permeabilization, reactive oxygen species formation, and a significant decrease in mitochondrial dehydrogenase activity and ATP content were evident in Mn-exposed (0.005-1 mM) brain mitochondria. On the other hand, ammonia (0.005-0.5 mM) caused no significant changes in brain mitochondrial function. It was found that co-exposure of the brain mitochondria to Mn and ammonia causes more evident mitochondrial impairment in comparison with Mn and/or ammonia alone.

Conclusions

These data indicate additive toxicity of ammonia and Mn in isolated brain mitochondria exposed to these neurotoxins.

The neuroprotective properties of carnosine in a mouse model of manganism is mediated via mitochondria regulating and antioxidative mechanisms

Objective(s): Manganese (Mn) is an essential trace element physiologically incorporated in the structure of several vital enzymes. Despite its essentiality, excessive Mn exposure is toxic with brain tissue as the primary target organ. There is no specific and clinically available therapeutic/preventive option against Mn neurotoxicity. Carnosine is a neuropeptide with several physiological roles. The neuroprotective properties of this peptide have been evaluated in different experimental models. The current study was designed to investigate the effect of carnosine supplementation and its potential mechanisms of action in an animal model of Mn-induced neurotoxicity. Materials and Methods: Male C57BL/6 mice received Mn (100 mg/kg, s.c) alone and/or in combination with carnosine (10, 50, and 100 mg/kg, i.p). Several locomotor activity indices were monitored. Moreover, biomarkers of oxidative stress and mitochondrial function were assessed in the brain tissue of Mn-exposed animals. Results: Significant locomotor dysfunction was revealed in Mn-exposed animals. Furthermore, brain tissue biomarkers of oxidative stress were significantly increased, and mitochondrial indices of functionality were impaired in Mn-treated animals. It was found that carnosine supplementation (10, 50, and 100 mg/kg, i.p) alleviated the Mn-induced locomotor deficit. Moreover, this peptide mitigated oxidative stress biomarkers and preserved brain tissue mitochondrial functionality in the animal model of manganism. Conclusion: These data indicate that carnosine is a potential neuroprotective agent against Mn neurotoxicity. Antioxidative and mitochondria protecting effects of carnosine might play a fundamental role in its neuroprotective properties against Mn toxicity.

The Role and Study of Mitochondrial Impairment and Oxidative Stress in Cholestasis

The blockage of bile flow, cholestasis, could lead to serious clinical outcomes, including severe liver injury. Accumulation of the cytotoxic molecules, such as bile acids, during cholestasis, not only impairs liver function, but also affects other organs, including the kidneys. Although the precise mechanisms of cytotoxicity and organ injury in cholestasis are far from clear, oxidative stress and its subsequent events seem to play a central role in this complication. Oxidative stress acts as a signaling path which could finally lead to cell death and organ injury. At the cellular level, mitochondria are major targets affected by cytotoxic molecules. Mitochondrial impairment could lead to severe outcomes, including cellular energy crisis and release of cell death mediators from this organelle. Therefore, targeting oxidative stress and mitochondrial dysfunction might serve as a therapeutic point of intervention against cholestasis-associated organ injury. In this protocol, an animal model of cholestasis is described, and the techniques for liver mitochondria isolation, evaluating mitochondrial indices of functionality, and assessing biomarkers of oxidative stress in the liver tissue are outlined.

Carnosine and Histidine Supplementation Blunt Lead-Induced Reproductive Toxicity through Antioxidative and Mitochondria-Dependent Mechanisms

Lead (Pb)-induced reproductive toxicity is a well-characterized adverse effect associated with this heavy metal. It has been found that Pb exposure is associated with altered spermatogenesis, increased testicular degeneration, and pathological sperm alterations. On the other hand, it has been reported that Pb-induced reproductive toxicity is associated with increased reactive oxygen species (ROS) formation and diminished antioxidant capacity in the reproductive system. Hence, administration of antioxidants as protective agents might be of value against Pb-induced reproductive toxicity. This study was designed to investigate whether carnosine (CAR) and histidine (HIS) supplementation would mitigate the Pb-induced reproductive toxicity in male rats. Animals received Pb (20 mg/kg/day, oral, 14 consecutive days) alone or in combination with CAR (250 and 500 mg/kg/day, oral, 14 consecutive days) or HIS (250 and 500 mg/kg/day, oral, 14 consecutive days). Pb toxicity was evident in the reproductive system by a significant increase in tissue markers of oxidative stress along with severe histopathological changes, seminal tubule damage, tubular desquamation, low spermatogenesis index, poor sperm parameters, and impaired sperm mitochondrial function. It was found that CAR and HIS supplementation blunted the Pb-induced oxidative stress and mitochondrial dysfunction in the rat reproductive system. Thereby, antioxidative and mitochondria-protective properties serve as primary mechanisms for CAR and HIS against Pb-induced reproductive toxicity.

Mechanism of valproic acid-induced Fanconi syndrome involves mitochondrial dysfunction and oxidative stress in rat kidney

AIM

Drug-induced kidney proximal tubular injury and renal failure (Fanconi syndrome; FS) is a clinical complication. Valproic acid (VPA) is among the FS-inducing drugs. The current investigation was designed to evaluate the role of mitochondrial dysfunction and oxidative stress in VPA-induced renal injury.

METHODS

Animals received VPA (250 and 500 mg/kg, i.p., 15 consecutive days). Serum biomarkers of kidney injury and markers of oxidative stress were assessed. Moreover, kidney mitochondria were isolated and mitochondrial indices, including succinate dehydrogenase activity (SDA), mitochondrial depolarization, mitochondrial permeability transition pore (MPP), reactive oxygen species (ROS), lipid peroxidation (LPO), mitochondrial glutathione, and ATP were determined.

RESULTS

Valproic acid-treated animals developed biochemical evidence of FS as judged by elevated serum gamma-glutamyl transferase (γ-GT), alkaline phosphatase (ALP), creatinine (Cr), and blood urea nitrogen (BUN) along with hypokalaemia, hypophosphataemia, and a decrease in serum uric acid. VPA caused an increase in kidney ROS and LPO. Renal GSH reservoirs were depleted and tissue antioxidant capacity decreased in VPA-treated animals. Renal tubular interstitial nephritis, tissue necrosis, and atrophy were also evident in VPA-treated rats. Mitochondrial parameters including SDA, MMP, GSH, ATP and MPP were decreased and mitochondrial ROS and LPO were increased with VPA treatment. It was found that carnitine (100 mg/kg, i.p.) mitigated VPA adverse effects towards the kidney.

CONCLUSIONS

These data suggest that mitochondrial dysfunction and oxidative stress contributed to the VPA-induced FS. On the other hand, carnitine could be considered a potentially safe and effective therapeutic option in attenuating VPA-induced renal injury.

Saturated fatty acids may ameliorate environmental heat stress in broiler birds by affecting mitochondrial energetics and related genes

Heat stress decreases performance of poultry. The novel strategies to maintain production level, or at least minimizing the decrease in productivity during hot days need to be elucidated. This study was conducted to determine the effect of four fat types on mitochondrial energetics in heat-stressed broilers. In experiment 1, nitrogen-corrected apparent metabolizable energy (AMEn) content of four supplemental fat sources, including olive oil, soybean oil, coconut oil and beef tallow, all supplemented at 3%, 6%, and 9% in the basal diet, was evaluated. The AMEn values of fats were determined as 9738.0 ± 137.9, 8949.0 ± 159.9, 7844.0 ± 91.7, and 7368.0 ± 190.3 kcal/kg for olive oil, soybean oil, coconut oil and beef tallow, respectively. In experiment 2, birds were kept in two separated rooms under 24 °C or 36 °C from 32 to 42 d of age. Each room consisted of four experimental groups. Birds in the experimental groups were fed on beef tallow-, coconut oil-, olive oil- or soybean oil-supplemented diets (factorial arrangement with two factors of fat types and environmental temperatures). The birds reared under 24 °C had higher final body weight (P < 0.01), weight gain (P < 0.01), feed intake (P < 0.05) and lower feed conversion ratio (P < 0.01) than the birds grown under 36 °C. There was a temperature by fat type interaction effect on mitochondrial attributes. At 36 °C, in birds fed on coconut oil- or beef tallow-supplemented diets, the expression levels of avUCP and avANT mRNA were lower (P < 0.05) but that of HSP70 mRNA was higher (P < 0.01) in comparison with the birds feeding on the olive oil- or soy oil-supplemented diets. An interaction effect was recorded between the temperature and fat type for ATP concentration and mitochondrial membrane potential (P < 0.01); with significant differences between birds receiving the coconut oil- or beef tallow-supplemented diets and the birds feeding on the soy oil- or olive oil-supplemented diets. It was also found that unsaturated fatty acids had a more significant effect on avUCP and avANT mRNA expression. It can be concluded that when using fat in the diet of heat stressed-broilers, it is advisable to choose a type, which has a lower effect on the expression of avUCP and avANT, and hence reduces the metabolic heat load in the bird.

Taurine prevents mitochondrial membrane permeabilization and swelling upon interaction with manganese: Implication in the treatment of cirrhosis-associated central nervous system complications

Brain tissue manganese (Mn) accumulation is a cirrhosis-associated complication. Cellular mitochondria are among the potential targets for Mn-induced cytotoxicity. Taurine is one of the most abundant amino acids with high concentrations in human brain tissue. Several pharmacological properties including regulation of mitochondrial function are attributed to taurine. The current investigation was designed to evaluate the effect of taurine on Mn-induced mitochondrial impairment in isolated mice brain mitochondria. The brain mitochondria were exposed to increasing concentrations of Mn (0.1-10 mM). Taurine (0.1, 1, and 10 mM) was added as the protective agent. The severe collapse of mitochondrial membrane potential, decreased mitochondrial dehydrogenases activity, mitochondrial swelling, and depleted mitochondrial adenosine triphosphate (ATP) were evident in Mn-exposed mitochondria. It was found that taurine administration preserved mitochondrial ATP, prevented mitochondrial depolarization and swelling, and increased mitochondrial dehydrogenases activity. These data suggest mitochondrial protection as an underlying mechanism for the protective effects of taurine against Mn toxicity.

Sulfasalazine induces mitochondrial dysfunction and renal injury

Sulfasalazine is a commonly used drug for the treatment of rheumatoid arthritis and inflammatory bowel disease. There are several cases of renal injury encompass sulfasalazine administration in humans. The mechanism of sulfasalazine adverse effects toward kidneys is obscure. Oxidative stress and its consequences seem to play a role in the sulfasalazine-induced renal injury. The current investigation was designed to investigate the effect of sulfasalazine on kidney mitochondria. Rats received sulfasalazine (400 and 600 mg/kg/day, oral) for 14 consecutive days. Afterward, kidney mitochondria were isolated and assessed. Sulfasalazine-induced renal injury was biochemically evident by the increase in serum blood urea nitrogen (BUN), gamma-glutamyl transferase (γ-GT), and creatinine (Cr). Histopathological presentations of the kidney in sulfasalazine-treated animals revealed by interstitial inflammation, tubular atrophy, and tissue necrosis. Markers of oxidative stress including an increase in reactive oxygen species (ROS) and lipid peroxidation (LPO), a defect in tissue antioxidant capacity, and glutathione (GSH) depletion were also detected in the kidney of sulfasalazine-treated groups. Decreased mitochondrial succinate dehydrogenase activity (SDA), mitochondrial depolarization, mitochondrial GSH depletion, increase in mitochondrial ROS, LPO, and mitochondrial swelling were also evident in sulfasalazine-treated groups. Current data suggested that oxidative stress and mitochondrial injury might be involved in the mechanism of sulfasalazine-induced renal injury.