Effect of N-Acetylcysteine on Dyslipidemia and Carbohydrate Metabolism in STZ-Induced Diabetic Rats

Cytokine profile and cholesterol levels in patients with Niemann-Pick type C disease presenting neurological symptoms: The in vivo effect of miglustat and the in vitro effect of N-acetylcysteine and Coenzyme Q10

Niemann Pick type C is an inborn error of metabolism (IEM), classified as a lysosomal storage disease (LSD) caused by a dysfunction in NPC transport protein, that leads to intracellular accumulation of non-esterified cholesterol and other lipids. Clinical manifestations are ample, with visceral and neurological symptoms. Miglustat, a molecule that reversibly inhibits glucosylceramide synthase is used as treatment for this disorder. Studies demonstrated the influence of oxidative stress and inflammation in IEM, as well in animal model of NP-C disease. Nonetheless, literature lacks data on patients, so our work aimed to investigate if there is influence of chronic inflammation in the pathophysiology of NP-C disease, and the effect of miglustat, N-acetylcysteine (NAC) and Coenzyme Q10 (CoQ10). We evaluated the plasmatic cytokines in NPC patients at diagnosis and during the treatment with miglustat. Additionally, we performed an in vitro study with antioxidants NAC (1 mM and 2.5 mM) and CoQ10 (5 μM and 10 μM), where we could verify its effect on inflammatory parameters, as well as in cholesterol accumulation. Our results showed that NP-C patients have higher plasmatic levels of pro and anti-inflammatory cytokines (IL-6, IL-8, and IL-10) at diagnosis and the treatment with miglustat was able to restore it. In vitro study showed that treatment with antioxidants in higher concentrations significantly decrease cholesterol accumulation, and NAC at 2.5 mM normalized the level of pro-inflammatory cytokines. Although the mechanism is not completely clear, it can be related to restoration in lipid traffic and decrease in oxidative stress caused by antioxidants.

N-Acetylcysteine: A Review of Clinical Usefulness (an Old Drug with New Tricks)

OBJECTIVE

To review the clinical usefulness of N-acetylcysteine (NAC) as treatment or adjunctive therapy in a number of medical conditions. Use in Tylenol overdose, cystic fibrosis, and chronic obstructive lung disease has been well documented, but there is emerging evidence many other conditions would benefit from this safe, simple, and inexpensive intervention. Quality of Evidence. PubMed, several books, and conference proceedings were searched for articles on NAC and health conditions listed above reviewing supportive evidence. This study uses a traditional integrated review format, and clinically relevant information is assessed using the American Family Physician Evidence-Based Medicine Toolkit. A table summarizing the potential mechanisms of action for N-acetylcysteine in these conditions is presented. Main Message. N-acetylcysteine may be useful as an adjuvant in treating various medical conditions, especially chronic diseases. These conditions include polycystic ovary disease, male infertility, sleep apnea, acquired immune deficiency syndrome, influenza, parkinsonism, multiple sclerosis, peripheral neuropathy, stroke outcomes, diabetic neuropathy, Crohn's disease, ulcerative colitis, schizophrenia, bipolar illness, and obsessive compulsive disorder; it can also be useful as a chelator for heavy metals and nanoparticles. There are also a number of other conditions that may show benefit; however, the evidence is not as robust.

CONCLUSION

The use of N-acetylcysteine should be considered in a number of conditions as our population ages and levels of glutathione drop. Supplementation may contribute to reducing morbidity and mortality in some chronic conditions as outlined in the article.

N-acetyl cysteine can blunt metabolic and cardiovascular effects via down-regulation of cardiotrophin-1 in rat model of fructose-induced metabolic syndrome

In this study, we investigated the ability of N-acetyl cysteine (NAC) to alleviate the metabolic disorders in fructose-induced metabolic syndrome (MS) in male rats and to examine its protective effect on aortic and cardiac tissues via its influence on cardiotrophin-1 (CT-1) expression. NAC (20 mg/kg b.w./day) was administered to fructose induced MS animals for 12 weeks. Chronic fructose consumption (20% w/v) increased body weight gain, relative heart weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), insulin resistance (IR), and associated with metabolic alterations. Histological and immunohistochemical examination revealed aortic stiffness and myocardial degeneration and fibrosis together with increased CT-1 expression. Treatment with NAC improved IR, SBP, DBP, and mitigated dyslipidaemia and oxidative stress. Additionally, NAC down-regulated CT-1 expression in the heart and aorta. These findings demonstrated the protective effect of NAC against aortic and myocardial degeneration and fibrosis through down-regulation of CT-1 in fructose induced MS animal model.

Comparative protective effects of N-acetylcysteine and melatonin against obesity-induced testicular dysfunction in rats

N-acetylcysteine (NAC) and melatonin were reported to exert protective effects on testicular tissues. Thus, this study aimed to determine which of these is more efficient against obesity-induced testicular dysfunction in albino rats. A total of 32 adult male rats (195 ± 10 g) were divided into four groups: control, obese rats fed a high-fat diet (HFD), HFD+NAC (150 mg/kg per day, i.p.) and HFD+melatonin (10 mg/kg per day, i.p.), for 5 weeks. Testes and epididymis were weighed. Lipid profile, pituitary-testicular hormones, tumor necrosis factor α (TNFα), epididymal sperm parameters, testicular oxidant-antioxidant system, testicular and the epididymal histopathology and immunohistochemical localization for androgen receptors (AR) and Bax reaction were analyzed. Administration of NAC or melatonin significantly improved the lipid parameters, gonadal hormones, TNFα level, sperm count and abnormal morphology, oxidant-antioxidant system and the absolute testicular and epididymal mass with an enhancement of testicular architecture, AR expression and apoptosis as compared with that in the obese group. Additionally, as compared with the NAC group, the melatonin group had significantly reduced body mass index, total cholesterol, triglyceride, and TNFα and increased testosterone, sperm count, motility, superoxide dismutase activity, mitigated histomorphometrical changes, Bax expression, and increased testicular AR expression. Therefore, melatonin was more efficient than NAC in affording fortification against HFD-induced testicular dysfunction.

Effect of long-term treatment of Carvacrol on glucose metabolism in Streptozotocin-induced diabetic mice

BACKGROUND

Carvacrol is a food additive with various bioactivities, including reducing the blood glucose level as well as improvement of heart function, in diabetic mice. We explored the antihyperglycemic effect of carvacrol and its effect on the key hepatic enzymes accounting for glucose metabolism.

METHODS

A streptozotocin (STZ)-induced diabetes-mellitus model in mice was used. Mice were divided randomly into a control group, diabetic group, low dose carvacrol-treated diabetic group (10 mg/kg body weight [BW]), and high dose carvacrol-treated diabetic group (20 mg/kg BW). Carvacrol was injected intraperitoneally (i.p.) in each carvacrol-treated group daily for 4 weeks and 6 weeks, respectively. The level of random plasma glucose, fasting plasma glucose, and plasma insulin was determined at 4 weeks and 6 weeks after carvacrol administration. The plasma level of total cholesterol (TC), triglycerides (TG), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), and the activity of hepatic key enzymes related to glucose metabolism were determined.

RESULTS

Carvacrol treatment decreased the levels of random plasma glucose and fasting plasma glucose, significantly in a dose-dependent manner. A significant improvement in glucose tolerance and a significant decrease in the plasma level of TG were observed in carvacrol-treated diabetic mice at a dose of 20 mg/kg BW compared with that in vehicle-treated diabetic mice. There was no significant difference in the plasma level of TC and insulin between vehicle-treated diabetic mice and carvacrol-treated diabetic mice. Carvacrol treatment at a dose of 20 mg/kg BW significantly reduced the plasma level of LDH but not AST, ALT, or ALP, compared with that in the vehicle-treated diabetic group. The activity of hexokinase (HK), 6-phosphofructokinase (PFK), and citrate synthetase (CS) was increased by carvacrol treatment in diabetic mice.

CONCLUSIONS

Carvacrol exerted an anti-hyperglycemic effect in STZ-induced diabetic mice. This was achieved through regulating glucose metabolism by increasing the activity of the hepatic enzymes HK, PFK, and CS.

Effect of propolis and N-acetylcysteine supplementation on lipoprotein subclasses distribution and paraoxonase 1 activity in subjects with acute respiratory infection

Background

Propolis and N-acetylcysteine have positive impact on respiratory tract health. Also, it has been suggested that they have beneficial effects on serum lipid and oxidative stress status, but the available data are limited and mostly gained from animal models. In this study we evaluated the effects of propolis and N-acetylcysteine supplementation (PropoMucil®) on lipid status, lipoprotein subclasses distribution and paraoxonase 1 activity in subjects with acute respiratory infection.

Methods

Twenty subjects with acute respiratory infection were included. PropoMucil® granules for oral solution (80 mg of dry propolis extract and 200 mg of N-acetylcysteine) were administered tree times per day for ten days. Serum lipid profile, paraoxonase 1 activity and low-density and high-density lipoprotein size and subclasses distribution were assessed at baseline and after supplementation.

Results

Following ten days of supplementation lipid status remained unchanged, but a significant increase of low-density lipoprotein particle size and proportion of high-density lipoprotein 3a particles were found (P<0.05). Moreover, supplementation with PropoMucil® significantly improved high-density lipoprotein particles distribution, particularly in those who smoke. There was a moderate increase of paraoxonase 1 activity, but without statistical significance.

Conclusions

The presented study demonstrated that short-term supplementation with PropoMucil® has beneficial effects on low-density and high-density lipoprotein subclasses distribution and paraoxonase 1 activity in subjects with acute respiratory infection particularly in those who smoke.

Ameliorative Effects Of N-Acetylcysteine As Adjunct Therapy On Symptoms Of Painful Diabetic Neuropathy

Purpose

Painful diabetic neuropathy (PDN) is a variant of diabetic peripheral neuropathy which is highly prevalent and distressing in diabetic patients. Despite its high burden, the optimal treatment of PDN has remained a clinical challenge. To explain the emergence and maintenance of PDN, increasing attention has been focused on dimensions of inflammation and oxidative toxic stress (OTS). Accordingly, the aim of this study was to investigate the effects of oral N-acetylcysteine (NAC), an agent with known anti-oxidant and anti-inflammatory effects, as an adjunct therapy in patients suffering from PDN.

Patients and methods

113 eligible patients with type 2 diabetes suffering from PDN were randomly assigned to either the pregabalin + placebo or pregabalin + NAC group for 8 weeks (pregabalin at a dose of 150 mg per day, NAC and matched placebo at doses of 600 mg twice a day). Mean pain score was evaluated at baseline, week 1, 2, 4, 6, and 8 of the study based on the mean 24 hr average pain score, using an 11-point numeric rating scale (NRS). As secondary efficacy measures, mean sleep interference score (SIS) resulting from PDN, responder rates, Patient Global Impression of Change (PGIC), Clinical Global Impression of Change (CGIC), and safety were also assessed. Additionally, serum levels of total antioxidant capacity (TAC), total thiol groups (TTG), catalase activity (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), nitric oxide (NO), and malondialdehyde (MDA) were assessed at baseline and at the end of the study.

Results

Ninety patients completed the eight-week course of the study. The decrease in mean pain scores and mean sleep interference score in pregabalin + NAC group was greater in comparison with pregabalin + placebo group (p value<0.001 in both conditions). Moreover, more responders (defined as ≥50% reduction in mean pain score from baseline to end-point) were observed in the pregabalin + NAC group, in comparison with pregabalin + placebo group (72.1% vs 46.8%). More improvement in PGIC and CGIC from baseline to the end of the study was reported in pregabalin + NAC group. Oral NAC had minimal adverse effects and was well tolerated in almost all patients. Furthermore, in respect to OTS biomarkers, adjuvant NAC significantly decreased serum level of MDA and significantly increased serum levels of SOD, GPx, TAC, and TTG.

Conclusion

The pattern of results suggests that compared to placebo and over a time period of 8 weeks, adjuvant NAC is more efficacious in improving neuropathic pain associated with diabetic neuropathy than placebo. Ameliorative effects of NAC on OTS biomarkers demonstrated that NAC may alleviate painful symptoms of diabetic neuropathy, at least in part by its antioxidant effects.

N-Acetyl cysteine ameliorates hyperglycemia-induced cardiomyocyte toxicity by improving mitochondrial energetics and enhancing endogenous Coenzyme Q9/10 levels

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Hyperglycemia is known to accelerate oxidative stress-induced myocardial injury.

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Mitochondrial energetics is an important mechanism to explore in the diabetic heart.

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NAC protects against hyperglycemia-induced cardiomyocyte toxicity.

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NAC improves mitochondrial energetics and enhances endogenous CoQ levels.

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CoQ supports the process of bioenergetics in addition to its antioxidant activities.

The diabetic heart has been linked with reduced endogenous levels of coenzyme Q_9/10 (CoQ), an important antioxidant and component of the electron transport chain. Although CoQ has displayed cardioprotective potential in experimental models of diabetes, the impact of N-acetyl cysteine (NAC) on mitochondrial energetics and endogenous levels of CoQ remains to be clarified. To explore these effects, high glucose-exposed H9c2 cardiomyocytes were used as an experimental model of hyperglycemia-induced cardiac injury. The results showed that high glucose exposure caused an increased production of reactive oxygen species (ROS), which was associated with impaired mitochondrial energetics as confirmed by a reduction of maximal respiration rate and depleted ATP levels. These detrimental effects were consistent with significantly reduced endogenous CoQ levels and accelerated cell toxicity. Although metformin demonstrated similar effects on mitochondrial energetics and cell viability, NAC demonstrated a more pronounced effect in ameliorating cytosolic and mitochondrial ROS production. Interestingly, the ameliorative effects of NAC against hyperglycemia-induced injury were linked with its capability to enhance endogenous CoQ levels. Although such data are to be confirmed in other models, especially in vivo studies, the overall findings provide additional evidence on the therapeutic mechanisms by which NAC protects against diabetes-induced cardiac injury.

Zingerone (4-(4-hydroxy-3-methylphenyl) butan-2-one) protects against alloxan-induced diabetes via alleviation of oxidative stress and inflammation: Probable role of NF-kB activation

Diabetes is considered as the most common metabolic disease affecting millions of people all around the world. Use of natural herbal medicines can be effective in treating diabetes. Zingerone (4-(4-hydroxy-3-methylphenyl) butan-2-one) a polyphenolic alkanone extracted from ginger has a broad spectrum of pharmacological properties and thus can be used as a promising candidate against various ailments. In the current study we aimed at demonstrating the protective effect of zingerone against diabetes mellitus and elucidating its possible mechanism. Five groups of animals (I-V) were made with ten animals each. Group I (control) was given normal saline orally. Group II (diabetic positive control) was given alloxan at the dose rate of 100 mg/kg bwt once. Group III and IV was given alloxan once at the dose rate of 100 mg/kg bwt. and received oral treatment of zingerone at a dose rate of 50 and 100 mg/kg bwt respectively daily for 21 days. Group V was given alloxan at the dose of 100 mg/kg bwt. and was treated with standard drug glibenclamide at the dose rate of 4.5 mg/kg bwt. daily for 21 days. According to our findings we confirmed that zingerone restrained the alloxan induced oxidative stress by increasing the activity of reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and reducing the peroxidative damage. We also confirmed that zingerone suppressed the level of redox sensitive transcription factor NFκB and downregulated other downstream inflammatory cytokines like interleukins (IL1-β IL-2, IL-6) and tumor necrosis factor alpha (TNF-α). Moreover, the experimental findings suggested that zingerone improved the insulin levels. Taken together our results indicated that zingerone effectively ameliorated the diabetes induced complications which provide a strong theoretical basis for zingerone to be used clinically for treatment of diabetes.