Upregulation of PPAR-γ mediates the renoprotective effect of omega-3 PUFA and ferulic acid in gentamicin-intoxicated rats

Molecular Mechanisms Linking Omega-3 Fatty Acids and the Gut-Brain Axis

The gut-brain axis (GBA) is a complex communication network connecting the gastrointestinal tract (GIT) and the central nervous system (CNS) through neuronal, endocrine, metabolic, and immune pathways. Omega-3 (n-3) fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are crucial food components that may modulate the function of this axis through molecular mechanisms. Derived mainly from marine sources, these long-chain polyunsaturated fatty acids are integral to cell membrane structure, enhancing fluidity and influencing neurotransmitter function and signal transduction. Additionally, n-3 fatty acids modulate inflammation by altering eicosanoid production, reducing proinflammatory cytokines, and promoting anti-inflammatory mediators. These actions help preserve the integrity of cellular barriers like the intestinal and blood-brain barriers. In the CNS, EPA and DHA support neurogenesis, synaptic plasticity, and neurotransmission, improving cognitive functions. They also regulate the hypothalamic-pituitary-adrenal (HPA) axis by reducing excessive cortisol production, associated with stress responses and mental health disorders. Furthermore, n-3 fatty acids influence the composition and function of the gut microbiota, promoting beneficial bacterial populations abundance that contribute to gut health and improve systemic immunity. Their multifaceted roles within the GBA underscore their significance in maintaining homeostasis and supporting mental well-being.

Naturally Occurring Compounds Targeting Peroxisome Proliferator Receptors: Potential Molecular Mechanisms and Future Perspectives for Promoting Human Health

Background: Peroxisome-proliferator-activated receptors (PPARs) constitute nuclear transcription factors controlling gene expression associated with cell growth and proliferation, diverse proteins, lipids, and glucose metabolism, being related to several other pathophysiological states such as metabolic disorders, atherogenesis, carcinogenesis, etc. The present survey aims to analyze the natural compounds that can act as agonists for the PPAR-α, PPAR-β/δ, and PPAR-γ system targeting, highlighting how the amazing biochemical diversity of natural compounds can yield new insights into this “hotspot” of the scientific field. Methods: A narrative review was performed by searching the recent international literature for the last two decades in the most authoritative scientific databases, like PubMed, Scopus, Web of Science, and Embase, using appropriate keywords. Results: Several natural compounds and/or their synthetic derivatives can act as ligands of PPARs, stimulating their transcriptional activity and enabling their use as preventive and/or therapeutic agents for several disease states, such as inflammation, oxidative stress, metabolic disturbances, atherogenesis, and carcinogenesis. Although synthetic compounds are increasingly used as drugs to manage health problems, serious side effects have been observed, while their natural analogues exhibit only few minor side effects. Conclusions: Further clinical studies on natural compounds such as ligands of PPARs and the evaluation of the related molecular mechanisms are needed to implement an effective strategy concerning the pharmaco-technology, food chemistry, and nutrition to introduce them as part of clinical and dietary practice.

Exploring the Role of Phenolic Compounds in Chronic Kidney Disease: A Systematic Review

Chronic kidney disease (CKD) presents a formidable global health concern, affecting one in six adults over 25. This review explores the potential of phenolic compounds in managing CKD and its complications. By examining the existing research, we highlight their diverse biological activities and potential to combat CKD-related issues. We analyze the nutritional benefits, bioavailability, and safety profile of these compounds. While the clinical evidence is promising, preclinical studies offer valuable insights into underlying mechanisms, optimal dosages, and potential side effects. Further research is crucial to validate the therapeutic efficacy of phenolic compounds for CKD. We advocate for continued exploration of their innovative applications in food, pharmaceuticals, and nutraceuticals. This review aims to catalyze the scientific community's efforts to leverage phenolic compounds against CKD-related challenges.

Allicin and Omega-3 fatty acids attenuates acetaminophen mediated renal toxicity and modulates oxidative stress, and cell apoptosis in rats

Acetaminophen (APAP), a widely used medication known for its pain-relieving and fever-reducing effects, can cause kidney failure if taken in excess. To investigate the potential protective effects of allicin (ALC) and/or omega-3 fatty acids (O3FA) against acetaminophen-induced kidney damage, a study was conducted using 49 rats divided into seven groups. The control group was given saline, while the other groups received ALC, O3FA, APAP, ALC + APAP, O3FA + APAP, or ALC + O3FA + APAP. After administering APAP, the rats showed decreased levels of total protein and albumin in their blood, along with increased levels of creatinine and urea. The concentration of reduced glutathione (GSH), as well as the activity of superoxide dismutase (SOD) and catalase (CAT), decreased, while the level of malondialdehyde (MDA) in the renal tissues increased. The activation of caspase-3 and HSP70 also suggested an impact on kidney histopathology. Overall, the study found that ALC and/or O3FA may have a protective impact against acetaminophen-induced kidney damage through their anti-inflammatory, anti-apoptotic, and antioxidant defense systems.

Bioactive compounds from Actinidia arguta fruit as a new strategy to fight glioblastoma

In recent years, there has been a significant demand for natural products as a mean of disease prevention or as an alternative to conventional medications. The driving force for this change is the growing recognition of the abundant presence of valuable bioactive compounds in natural products. On recent years Actinia arguta fruit, also known as kiwiberry, has attracted a lot of attention from scientific community due to its richness in bioactive compounds, including phenolic compounds, organic acids, vitamins, carotenoids and fiber. These bioactive compounds contribute to the fruit's diverse outstanding biological activities such as antioxidant, anti-inflammatory, neuroprotective, immunomodulatory, and anti-cancer properties. Due to these properties, the fruit may have the potential to be used in the treatment/prevention of various types of cancer, including glioblastoma. Glioblastoma is the most aggressive form of brain cancer, displaying 90 % of recurrence rate within a span of 2 years. Despite the employment of an aggressive approach, the prognosis remains unfavorable, emphasizing the urgent requirement for the development of new effective treatments. The preclinical evidence suggests that kiwiberry has potential impact on glioblastoma by reducing the cancer self-renewal, modulating the signaling pathways involved in the regulation of the cell phenotype and metabolism, and influencing the consolidation of the tumor microenvironment. Even though, challenges such as the imprecise composition and concentration of bioactive compounds, and its low bioavailability after oral administration may be drawbacks to the development of kiwiberry-based treatments, being urgent to ensure the safety and efficacy of kiwiberry for the prevention and treatment of glioblastoma. This review aims to highlight the potential impact of A. arguta bioactive compounds on glioblastoma, providing novel insights into their applicability as complementary or alternative therapies.

Dry heat whole Sorghum BRS 305 flour modulate satiety and improves antioxidant response in brain of Wistar rats fed with high-fat high-fructose diet

Sorghum BRS 305 (Sorghum bicolor L. Moench) is a cereal with high tannins and anthocyanins content and keep better the resistant starch when submitted to dry heat treatment. Our objective was to investigate the effects of BRS 305 dry heat treatment whole sorghum flour on satiety and antioxidant response in brain and adipose tissue of Wistar rats fed with a high fat high fructose diet (HFHF). Male Wistar rats were divided in two groups: control (n = 8) and HFHF (n = 16) for eight weeks. After, animals of HFHF group were divided: HFHF (n = 8) and HFHF + BRS 305 sorghum whole flour (n = 8), for 10 weeks. Sorghum consumption reduced gene expression of leptin, resistin, and endocannabinoid receptor 1 type (CB1) in adipose and brain tissues compared to HFHF group. In brain, sorghum consumption also promotes reduction in neuropeptide Y (NPY) gene expression. BRS305 sorghum consumption improved gene expression of sirtuin-1 (SIRT1) in adipose tissue, and in the brain increased heat shock protein 72 (HSP72), erythroid-derived nuclear factor 2 (NRF2), peroxisome proliferator-activated receptor alpha (PPARα), superoxide dismutase (SOD) and catalase activity compared to HFHF. In silicoanalysis showed interaction with PPARα, CB1, and leptin receptors. Advanced glycation end products (AGEs) concentrations in group HFHF + sorghum did not differ from HFHF group. Advanced glycation end products receptors (RAGEs) concentrations did not differ among experimental groups. Then, BRS 305 sorghum submitted to dry treatment was able to modulate gene expression of markers related to satiety and improve antioxidant capacity of rats fed with HFHF diet.

The Therapeutic Potential of Hydroxycinnamic Acid Derivatives in Parkinson's Disease: Focus on In Vivo Research Advancements

Hydroxycinnamic acid derivatives (HCDs) are polyphenols that are abundant in cereals, coffee, tea, wine, fruits, vegetables, and other plant-based foods. To aid in the clinical prevention and treatment of Parkinson's disease (PD), we evaluated in vivo investigations of the pharmacological properties of HCDs relevant to PD, and their pharmacokinetic and safety aspects. An extensive search of published journals was conducted using several literature databases, including PubMed, Google Scholar, and the Web of Science. The search terms included "hydroxycinnamic acid derivatives," "ferulic acid," "caffeic acid," "sinapic acid," "p-coumaric acid," "Parkinson's disease," and combinations of these keywords. As of April 2023, 455 preclinical studies were retrieved, of which 364 were in vivo studies; we included 17 of these articles on the pharmaceutics of HCDs in PD. Available evidence supports the protective effects of HCDs in PD due to their anti-inflammatory, antioxidant, as well as antiapoptotic physiological activities. Studies have identified possible molecular targets and pathways for the protective actions of HCDs in PD. However, the paucity of studies on these compounds in PD, and the risk of toxicity induced with high-dose applications, limits their use. Thus, multifaceted studies of HCDs in vitro and in vivo are needed.

Hepatoprotective and anti-hyperglycemic effects of ferulic acid in arsenic-exposed mice

Arsenic is a toxic metalloid that increases the risk of hepatotoxicity and hyperglycemia. The objective of the present study was to assess the effect of ferulic acid (FA) in mitigating glucose intolerance and hepatotoxicity caused by sodium arsenite (SA). A total of six groups including control, FA 100 mg/kg, SA 10 mg/kg, and groups that received different doses of FA (10, 30, and 100 mg/kg), respectively just before SA (10 mg/kg) for 28 days were examined. Fasting blood sugar (FBS) and glucose tolerance tests were conducted on the 29th day. On day 30, mice were sacrificed and blood and tissues (liver and pancreas) were collected for further investigations. FA reduced FBS and improved glucose intolerance. Liver function and histopathological studies confirmed that FA preserved the structure of the liver in groups received SA. Furthermore, FA increased antioxidant defense and decreased lipid peroxidation and tumor necrosis factor-alpha level in SA-treated mice. FA, at the doses of 30 and 100 mg/kg, prevented the decrease in the expression of PPAR-γ and GLUT2 proteins in the liver of mice exposed to SA. In conclusion, FA prevented SA-induced glucose intolerance and hepatotoxicity by reducing oxidative stress, inflammation, and hepatic overexpression of PPAR-γ and GLUT2 proteins.

Dietary regulation of peroxisome proliferator-activated receptors in metabolic syndrome

BACKGROUND

Peroxisome proliferator-activated receptors (PPARs) are a class of ligand-activated nuclear transcription factors, members of the type nuclear receptor superfamily, with three subtypes, namely PPARα, PPARβ/δ, and PPARγ, which play a key role in the metabolic syndrome. In the past decades, a large number of studies have shown that natural products can act by regulating metabolic pathways mediated by PPARs.

PURPOSE

This work summarizes the physiological importance and clinical significance of PPARs and reviews the experimental evidence that natural products mediate metabolic syndrome via PPARs.

METHODS

This study reviews relevant literature on clinical trials, epidemiology, animals, and cell cultures published in NCBI PubMed, Scopus, Web of Science, Google Scholar, and other databases from 2001 to October 2022. Search keywords were "natural product" OR "botanical" OR "phytochemical" AND "PPAR" as well as free text words.

RESULTS

The modulatory involvement of PPARs in the metabolic syndrome has been supported by prior research. It has been observed that many natural products can treat metabolic syndrome by altering PPARs. The majority of currently described natural compounds are mild PPAR-selective agonists with therapeutic effects that are equivalent to synthetic medicines but less harmful adverse effects.

CONCLUSION

PPAR agonists can be combined with natural products to treat and prevent metabolic syndrome. Further human investigations are required because it is unknown how natural products cause harm and how they might have negative impacts.

Potential therapeutic effects of Chinese meteria medica in mitigating drug-induced acute kidney injury

Drug-induced acute kidney injury (DI-AKI) is one of the leading causes of kidney injury, is associated with high mortality and morbidity, and limits the clinical use of certain therapeutic or diagnostic agents, such as antineoplastic drugs, antibiotics, immunosuppressants, non-steroidal anti-inflammatory drugs, and contrast media. In recent years, numerous studies have shown that many Chinese meteria medica, metabolites derived from botanical drugs, and Chinese medicinal formulas confer protective effects against DI-AKI by targeting a variety of cellular or molecular mechanisms, such as oxidative stress, inflammatory, cell necrosis, apoptosis, and autophagy. This review summarizes the research status of common DI-AKI with Chinese meteria medica interventions, including cisplatin, gentamicin, contrast agents, methotrexate, and acetaminophen. At the same time, this review introduces the metabolites with application prospects represented by ginseng saponins, tetramethylpyrazine, panax notoginseng saponins, and curcumin. Overall, this review provides a reference for the development of promising nephroprotectants.

Influence of omega- 3 fatty acids, soya isoflavones and their combination for abrogating carbon tetrachloride hazards in male rats

Studies have shown that carbon tetrachloride (CCl4) induces hepatic and renal damage arising from oxidative stress. The present study was undertaken to examine the effect of omega-3 fatty acids and/or soya isoflavones on CCl4 induced toxicity in male albino rat liver and kidney. For this purpose, 42 rats were divided as follows: group 1, rats serves as the control without any treatment; group 2, rats were administered a single dose of CCl4 intraperitoneally (1 mg/kg b. wt.); group 3, rats were supplemented daily with omega-300 orally (400 mg/kg b. wt.); group 4, rats were supplemented daily with pro-S orally (50 mg/kg b. wt.); group 5, rats were supplemented daily with omega-300 orally for four weeks, then after 24 hours treated with a single dose of CCl4 at the same tested doses. group 6, rats were supplemented daily with pro- S orally for four weeks, then after 24 hours treated with a single dose of CCl4 at the same tested doses; group 7, rats were supplemented daily with an oral combination of omega-300 and pro-S orally for four weeks, then after 24 hours treated with a single dose of CCl4 at the same tested doses. Results showed that CCl4 administration induces hepatic damage indicated by a significant increase in the activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST) and Aalanine aminotransferase (ALT) enzymes and glucose level, with a significant increase in malondialdehyde (MDA) and nitric oxide (NO) levels and a significant decrease of reduced glutathione (GSH) level in liver tissue. Also, CCl4 toxicity induce renal damage manifested in a significant increase in serum urea, creatinine, uric acid, and oxidative stress of kidney tissue reflected by increase of MDA, NO and the decrease of GSH levels. The pre-treatment with omega-3 fatty acids and/or soya isoflavones revealed ameliorative effect against deleterious effects of CCl4 toxicity on hepatic and renal tissues and all tested parameters. Results of the current study revealed also that the pre-treatment with omega-3 fatty acids and/or soya isoflavones to rats improved liver and kidney function and produced high antioxidant activity.

Methotrexate-Induced Alteration of Renal Aquaporins 1 and 2, Oxidative Stress and Tubular Apoptosis Can Be Attenuated by Omega-3 Fatty Acids Supplementation

Methotrexate (MTX) is a potent anti-cancer drug, commonly associated with nephrotoxicity via the induction of oxidative stress and apoptosis with alteration of renal water channel proteins, namely aquaporins (AQPs). Omega-3 long-chain polyunsaturated fatty acids (LC-PUFA) have shown cytoprotective effects through their anti-oxidant and antiapoptotic activities. The present study aims for the first time to explore the role of LC-PUFA against MTX-induced nephrotoxicity. Rats were divided into the following groups: saline control, LC-PUFA control, MTX, MTX + LC-PUFA (150 mg/kg), or MTX + LC-PUFA (300 mg/kg). Then, H&E staining and immunohistochemical staining for the anti-apoptosis marker B-cell lymphoma 2 (BCL-2), the apoptosis marker BCL2-Associated X Protein (BAX), the proinflammatory marker Nuclear factor kappa B (NF-kB), AQPs 1 and 2 were performed in kidney sections with an assessment of renal oxidative stress. The MTX caused a renal histopathological alteration, upregulated renal BAX and NF-kB, downregulated Bcl-2 and AQP1, altered the distribution of AQP2, and caused oxidative stress. The LC-PUFA attenuated the pathological changes and decreased renal BAX and NF-kB, increased BCL-2 and AQP1, restored the normal distribution of AQP2, and decreased the oxidative stress. Therefore, LC-PUFA is a good adjuvant to MTX to prevent its adverse effects on kidneys through its antiapoptotic, antioxidant, and anti-inflammatory effect and its role in the restoration of the expression of AQPs 1 and 2.

Peroxisome proliferator-activated receptor gamma and its natural agonists in the treatment of kidney diseases

Kidney disease is one of the leading non-communicable diseases related to tremendous health and economic burden globally. Diabetes, hypertension, obesity and cardiovascular conditions are the major risk factors for kidney disease, followed by infections, toxicity and autoimmune causes. The peroxisome proliferator-activated receptor gamma (PPAR-γ) is a ligand-activated nuclear receptor that plays an essential role in kidney physiology and disease. The synthetic agonists of PPAR-γ shows a therapeutic effect in various kidney conditions; however, the associated side effect restricts their use. Therefore, there is an increasing interest in exploring natural products with PPARγ-activating potential, which can be a promising solution to developing effective and safe treatment of kidney diseases. In this review, we have discussed the role of PPAR-γ in the pathophysiology of kidney disease and the potential of natural PPAR-γ agonists in treating various kidney diseases, including acute kidney injury, diabetic kidney disease, obesity-induced nephropathy, hypertension nephropathy and IgA nephropathy. PPAR-γ is a potential target for the natural PPAR-γ agonists against kidney disease; however, more studies are required in this direction.

The Enteric Glia and Its Modulation by the Endocannabinoid System, a New Target for Cannabinoid-Based Nutraceuticals?

The enteric nervous system (ENS) is a part of the autonomic nervous system that intrinsically innervates the gastrointestinal (GI) tract. Whereas enteric neurons have been deeply studied, the enteric glial cells (EGCs) have received less attention. However, these are immune-competent cells that contribute to the maintenance of the GI tract homeostasis through supporting epithelial integrity, providing neuroprotection, and influencing the GI motor function and sensation. The endogenous cannabinoid system (ECS) includes endogenous classical cannabinoids (anandamide, 2-arachidonoylglycerol), cannabinoid-like ligands (oleoylethanolamide (OEA) and palmitoylethanolamide (PEA)), enzymes involved in their metabolism (FAAH, MAGL, COX-2) and classical (CB1 and CB2) and non-classical (TRPV1, GPR55, PPAR) receptors. The ECS participates in many processes crucial for the proper functioning of the GI tract, in which the EGCs are involved. Thus, the modulation of the EGCs through the ECS might be beneficial to treat some dysfunctions of the GI tract. This review explores the role of EGCs and ECS on the GI tract functions and dysfunctions, and the current knowledge about how EGCs may be modulated by the ECS components, as possible new targets for cannabinoids and cannabinoid-like molecules, particularly those with potential nutraceutical use.

Recent Advances in the Neuroprotective Properties of Ferulic Acid in Alzheimer's Disease: A Narrative Review

Alzheimer's disease (AD) is a progressive degenerative disorder of the central nervous system, characterized by neuroinflammation, neurotransmitter deficits, and neurodegeneration, which finally leads to neuronal death. Emerging evidence highlighted that hyperglycemia and brain insulin resistance represent risk factors for AD development, thus suggesting the existence of an additional AD form, associated with glucose metabolism impairment, named type 3 diabetes. Owing to the limited pharmacological options, novel strategies, especially dietary approaches based on the consumption of polyphenols, have been addressed to prevent or, at least, slow down AD progression. Among polyphenols, ferulic acid is a hydroxycinnamic acid derivative, widely distributed in nature, especially in cereal bran and fruits, and known to be endowed with many bioactivities, especially antioxidant, anti-inflammatory and antidiabetic, thus suggesting it could be exploited as a possible novel neuroprotective strategy. Considering the importance of ferulic acid as a bioactive molecule and its widespread distribution in foods and medicinal plants, the aim of the present narrative review is to provide an overview on the existing preclinical and clinical evidence about the neuroprotective properties and mechanisms of action of ferulic acid, also focusing on its ability to modulate glucose homeostasis, in order to support a further therapeutic interest for AD and type 3 diabetes.

Ferulic acid: A review of its pharmacology, pharmacokinetics and derivatives

Ferulic acid, a kind of phenolic substance widely existing in plants, is an important active component of many traditional Chinese medicines. So far, it has been proved that ferulic acid has a variety of biological activities, especially in oxidative stress, inflammation, vascular endothelial injury, fibrosis, apoptosis and platelet aggregation. Many studies have shown that ferulic acid can inhibit PI3K/AKT pathway, the production of ROS and the activity of aldose reductase. The anti-inflammatory effect of ferulic acid is mainly related to the levels of PPAR γ, CAM and NF-κ B and p38 MAPK signaling pathways. Ferulic acid not only protects vascular endothelium by ERK1/2 and NO/ET-1 signal, but also plays an anti-fibrosis role by TGF-β/Smad and MMPs/TIMPs system. Moreover, ferulic acid has ant-apoptotic and anti-platelet effects. In addition to the pharmacological effects of ferulic acid, its pharmacokinetics and derivatives were also discussed in this paper. This review provides the latest summary of the latest research on ferulic acid.

Umbelliferone attenuates glycerol-induced myoglobinuric acute kidney injury through peroxisome proliferator-activated receptor-γ agonism in rats

Rhabdomyolysis is a clinical syndrome caused by damage to skeletal muscle, which consequently releases breakdown products into circulation and causes acute kidney injury (AKI) in humans. Intramuscular injection of glycerol mimics rhabdomyolysis and associated AKI. In this study, we explored the role of umbelliferone against glycerol-induced AKI in rats. Kidney function was assessed by measuring serum creatinine, urea, electrolytes, and microproteinuria. Renal oxidative stress was quantified using thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione assay. Renal histological changes were determined using periodic acid Schiff and hematoxylin-eosin staining, and immunohistology of apoptotic markers (Bax, Bcl-2) was done. Serum creatine kinase was quantified to assess glycerol-induced muscle damage. Umbelliferone attenuated glycerol-induced change in biochemical parameters, oxidative stress, histological alterations, and renal apoptosis. Pretreatment with bisphenol A diglycidyl ether, a peroxisome proliferator-activated receptor-γ (PPAR-γ) antagonist, attenuated umbelliferone-mediated protection. It is concluded that umbelliferone attenuates glycerol-induced AKI possibly through PPAR-γ agonism in rats.

Effect of zinc oxide nanoparticles and ferulic acid on renal ischemia/reperfusion injury: possible underlying mechanisms

OBJECTIVES

The present study examined the effects of ferulic acid (FA) and Zinc oxide nanoparticles (ZnO-NPs) and a combination of both on renal ischemia/reperfusion injury (IRI) in rats and their possible underlying mechanisms.

METHODS

two-hundreds male Sprague Dawley rats were randomly allocated into the 5 groups; i) sham group, ii) control (IRI) group (occlusion of the left renal pedicle for 45 min), iii) FA group as IRI group with FA (100 mg/Kg oral 24 hrs before ischemia), iv) ZnO-NPs group as IRI group with ZnO-NPs single 5 mg/Kg i.p. 2 hrs before ischemia and v) FA + ZnO-NPs group as IRI group with both FA and ZnO-NPs in the same previous doses. According to the reperfusion times, each group was further subdivided into 4 hr, 24 hr, 48 hr and 7 days reperfusion subgroups.

RESULTS

administration of either FA or ZnO-NPs caused significant improvement in the elevated serum creatinine and BUN and malondialdehyde (MDA) concentrations and expression of TNF-α, Bax, caspase-3 in kidney tissues with significant rise in the creatinine clearance, the activities of catalase (CAT) and superoxide dismutase (SOD) and the expression of HO-1, HIF-1α genes and proliferation marker (ki67) in kidney tissues compared to IRI group (p < 0.05). Moreover, a combination of both agents produced more significant improvement in the studied parameters than each agent did alone (p < 0.05).

CONCLUSIONS

Both FA and ZnO-NPs exerted cytoprotective effects against ischemic kidney injury and a combination of both exhibited more powerful renoprotective effect. This renoprotective effect might be due to suppression of oxidative stress, enhancement of cell proliferation (ki67), upregulation of antioxidant genes (Nrf2, HO-1 and HIF-1α) and downregulation of inflammatory cytokine (TNF-α) and apoptotic genes (caspase-3 and Bax).

Protective effects of natural products against drug-induced nephrotoxicity: A review in recent years

Drug-induced nephrotoxicity (DIN) is a major cause of kidney damage and is associated with high mortality and morbidity, which limits the clinical use of certain therapeutic or diagnostic agents, such as antineoplastic drugs, antibiotics, immunosuppressive agents, non-steroidal anti-inflammatory drugs (NSAIDs), and contrast agents. However, in recent years, a number of studies have shown that many natural products (NPs), including phytochemicals, various plants extracts, herbal formulas, and NPs derived from animals, confer protective effects against DIN through multi-targeting therapeutic mechanisms, such as inhibition of oxidative stress, inflammation, apoptosis, fibrosis, and necroptosis, regulation of autophagy, maintenance of cell polarity, etc., by regulating multiple signaling pathways and novel molecular targets. In this review, we summarize and discuss the protective effects and mechanisms underlying the action of NPs against DIN found in recent years, which will contribute to the development of promising renal protective agents.

NLRP3 Inflammasome: A Promising Therapeutic Target for Drug-Induced Toxicity

Drug-induced toxicity, which impairs human organ function, is a serious problem during drug development that hinders the clinical use of many marketed drugs, and the underlying mechanisms are complicated. As a sensor of infections and external stimuli, nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain containing 3 (NLRP3) inflammasome plays a key role in the pathological process of various diseases. In this review, we specifically focused on the role of NLRP3 inflammasome in drug-induced diverse organ toxicities, especially the hepatotoxicity, nephrotoxicity, and cardiotoxicity. NLRP3 inflammasome is involved in the initiation and deterioration of drug-induced toxicity through multiple signaling pathways. Therapeutic strategies via inhibiting NLRP3 inflammasome for drug-induced toxicity have made significant progress, especially in the protective effects of the phytochemicals. Growing evidence collected in this review indicates that NLRP3 is a promising therapeutic target for drug-induced toxicity.

Targeting KEAP1/Nrf2, AKT, and PPAR-γ signals as a potential protective mechanism of diosmin against gentamicin-induced nephrotoxicity

AIM

Gentamicin (GM) is an aminoglycoside antibiotic effectively used for severe/life-threatening infections. However, the clinical application of GM is limited by nephrotoxic side effects. Diosmin (DS) is a flavonoid with a wide range of bioactivities. However, its therapeutic potential in GM-induced nephrotoxicity remains unclear.

METHODS

Rats received GM (100 mg/kg, i.p.) for 7 days either separately or in combination with oral DS (50 mg/kg).

RESULTS

GM injection disrupted kidney function along with oxidant/antioxidant imbalance. Also, GM significantly decreased renal nuclear factor erythroid 2-related factor 2 (Nrf2), glutamyl cysteine synthetase (GCLC), heme oxygenase-1 (HO-1), superoxide dismutase3 (SOD-3), protein kinase B (AKT), and p-AKT expressions along with Kelch-like ECH-associated protein 1 (KEAP1) up-regulation. On the contrary, DS administration significantly attenuated GM-induced kidney dysfunction and restored kidney oxidant/antioxidant status. In addition, co-treatment with DS plus GM significantly enhanced Nrf2, GCLC, HO-1, SOD3, AKT, and p-AKT expressions along with KEAP1 down-regulation. Additionally, GM-treated rats exhibited a significant decrease in the expressions of renal peroxisome-proliferator activated receptor-gamma (PPAR-γ) and this reduction was alleviated by DS treatment. Furthermore, histopathological findings demonstrated that DS significantly reduced the GM-induced histological abrasions. Besides, an in-silico study was conducted to confirm our biochemical results. Interestingly, in-silico results strongly supported our biochemical investigation by studying the binding affinity of DS to KEAP1, AKT, and PPAR-γ proteins.

SIGNIFICANCE

DS could be a promising protective agent against GM-induced nephrotoxicity through targeting of KEAP1/Nrf2/ARE, AKT, and PPAR-γ signaling pathways.

The influence of omega-3 supplementation on vitamin D levels in humans: a systematic review and dose-response meta-analysis of randomized controlled trials

BACKGROUND

Inconsistencies exist with regard to the influence of omega-3 supplementation on 25-hydroxyvitamin D (25(OH)D) levels, which could be attributed to many factors, such as the duration and dose of omega-3 supplementation, and individuals' baseline 25(OH)D levels. Therefore, to address the inconsistencies, we conducted a systematic review and dose-response meta-analysis to accurately determine the effect of omega-3 supplementation on 25(OH)D levels in humans.

METHODS

We performed a comprehensive literature search in Web of Science, PubMed/Medline, Scopus, and Embase databases from inception up to January 2020. We included only randomized controlled trials (RCTs). We used weighted mean difference (WMD) with 95% confidence interval (CI) to assess the influence of omega-3 supplementation on serum 25(OH)D levels using the random-effects model.

RESULTS

Our pooled results of 10 RCTs demonstrated an overall significant increase in 25(OH)D levels following omega-3 intake (WMD = 3.77 ng/ml, 95% CI: 1.29, 6.25). In addition, 25(OH)D levels were significantly increased when the intervention duration lasted >8 weeks and when the baseline serum 25(OH)D level was ˂20 ng/ml. Moreover, omega-3 intake ≤1000 mg/day resulted in higher 25(OH)D levels compared to omega-3 intake >1000 mg/day.

CONCLUSION

In conclusion, omega-3 supplementation increased 25(OH)D concentrations, particularly with dosages ≤1000 mg/day and intervention durations >8 weeks.

Omega-3 fatty acids ameliorate doxorubicin-induced cardiorenal toxicity: In-vivo regulation of oxidative stress, apoptosis and renal Nox4, and in-vitro preservation of the cytotoxic efficacy

This study examines the protective effects of omega-3 fatty acids (OMG), a frequently used nutritional therapy in cancer patients, against doxorubicin (DOX)-induced acute cardiorenal toxicity in rats, and evaluates the cytotoxic activity of DOX when used with OMG against breast cancer cell line. Five groups of rats were treated for 4 consecutive weeks with vehicle (groups I & II), or OMG (25, 50 or 100 mg/kg/day, po; groups III, IV & V, respectively). After twenty-four hours, the last four groups were injected with DOX (200 mg/kg, ip). In DOX-treated rats, the altered ECG, serum cardiac and renal function biomarkers, and histopathological features indicated the induction of cardiorenal toxicity. Increased oxidative and apoptotic markers in both organs was observed, with elevated renal contents of NADPH-oxidase-4 (Nox4) and renin. OMG pretreatment improved those DOX-induced impairments in a dose-dependent manner, and showed antioxidant and antiapoptotic effects with regulation of renal Nox4 expression. The in-vitro study showed preservation of the cytotoxic activity of DOX on MCF7 cell line in the presence of OMG. The data suggests OMG for protection against acute DOX-induced cardiorenal damage without affecting the latter antitumor activity. It proposes regulation of oxidative stress, Nox4 activity and apoptosis as contributing protective mechanisms.

Omega-3 fatty acids protect against acetaminophen-induced hepatic and renal toxicity in rats through HO-1-Nrf2-BACH1 pathway

Although acetaminophen (APAP) is a commonly used analgesic antipyretic drug, hepatotoxicity and nephrotoxicity are common after the overdose. The main mechanism of APAP toxicity is oxidative stress based. Stress may induce the production of heme oxygenase 1 (HO)-1 which is regulated by interleukin (IL)-10 and inhibit the production of tumor necrosis factor-alpha (TNF-α). HO-1 expression is further regulated by nuclear factor erythroid 2-related factor 2 (Nrf2) and the transcription factor BTB and CNC homology 1 (BACH1). Drug-induced toxicity can be relieved by several natural products, which are preferred due to their dietary nature and less adverse reactions. Of these natural products, omega-3 (ω-3) fatty acids are known for anti-inflammatory and antioxidant actions. However, effects of ω-3fatty acids on APAP-induced hepatic and renal toxicity are not well addressed. We designed this study to test the potential protecting actions of ω-3 fatty acids (270 mg/kg Eicosapentaenoic acid and 180 mg/kg docosahexaenoic acid, orally, for 7 days) in hepatotoxicity and nephrotoxicity induced by APAP (2 g/kg, once orally on day 7) in rats. Moreover, we focused on the molecular mechanism underlying APAP hepatotoxicity and nephrotoxicity. Pre-treatment with ω-3 fatty acids enhanced liver and kidney functions indicated by decreased serum aminotransferases activities and serum creatinine and urea concentrations. These results were further confirmed by histopathological examination. Moreover, ω-3 fatty acids showed antioxidant properties confirmed by decreased malondialdehyde level and increased total antioxidant capacity. Antioxidant Nrf2, its regulators (HO-1 and BACH1) and the anti-inflammatory cytokine (IL-10) were up-regulated by APAP administration as a compensatory mechanism and they were normalized by ω-3 fatty acids. ω-3 fatty acids showed anti-inflammatory actions through down-regulating nuclear factor kappa B (NF-ĸB) and its downstream TNF-α. Moreover, Western blot analysis showed that ω-3 fatty acids promoted Nrf2 translocation to the nucleus; BACH1 exit from the nucleus and inhibited NF-ĸB nuclear translocation. These findings suggested the protecting actions of ω-3 fatty acids against APAP-induced hepatic and renal toxicity through regulation of antioxidant Nrf2 and inflammatory NF-ĸB pathways.

Sinapic acid attenuates cisplatin-induced nephrotoxicity through peroxisome proliferator-activated receptor gamma agonism in rats

AIM

The aim of this study was to investigate the involvement of peroxisome proliferator-activated receptor gamma (PPAR-γ) in renal protection offered by sinapic acid in cisplatin-induced nephrotoxicity in male rats.

MATERIALS AND METHODS

Nephrotoxicity was induced by single dose of cisplatin (5 mg/kg, intraperitoneal [i.p.]) in rats. Cisplatin-induced nephrotoxicity was assessed by measuring serum creatinine, creatinine clearance, urea, uric acid, potassium, magnesium levels, fractional excretion of sodium, and microproteinuria in rats. Superoxide anion generation, thiobarbituric acid reactive substances, myeloperoxidase activity, and reduced glutathione levels were measured to assess oxidative stress in renal tissues. Hematoxylin and eosin stain showed renal histological changes.

RESULTS

The significant changes in serum and urinary parameters, elevated oxidative stress, and renal histological changes established the induction of nephrotoxicity. Sinapic acid treatment (20 and 40 mg/kg, orally [p.o.]) provides dose-dependent and significant (P < 0.05) nephroprotection against cisplatin-mediated nephrotoxicity in rats. Nephroprotective effect of sinapic acid was abolished by PPAR-γ inhibitor, bisphenol A diglycidyl ether (30 mg/kg, i.p.) in rats.

CONCLUSION

It is concluded that PPAR-γ agonism serves as one of the mechanisms in sinapic acid-mediated renoprotection.

Phenylpropanoids and its derivatives: biological activities and its role in food, pharmaceutical and cosmetic industries

Phenylpropanoids and their derivatives are plant secondary metabolites widely present in fruits, vegetables, cereal grains, beverages, spices and herbs. They are known to have multifaceted effects which include antimicrobial, antioxidant, anti-inflammatory, antidiabetic, anticancer activities and as well as exhibits renoprotective, neuroprotective, cardioprotective and hepatoprotective effects. Owing to their antioxidant, antimicrobial and photoprotective properties, these compounds have wide application in the food (preservation, packaging films and edible coating), pharmaceutical, cosmetic and other industries such as textile (colorant), biofuel (antioxidant additive) and sensors (sensing biologically relevant molecules). Phenylpropanoids are present in commercially available dietary supplements and skin care products. In this review, we have presented the current knowledge on the biosynthesis, occurrence, biological activities of phenylpropanoids and their derivatives, along with the mechanism of action and their potential applications in various industries.

Partitioning of Rumen-Protected n-3 and n-6 Fatty Acids is Organ-Specific in Growing Angus Heifers

Dietary polyunsaturated fatty acids (PUFA), especially n-3 and n-6 fatty acids (FA), play an important role in the regulation of FA metabolism in all mammals. However, FA metabolism differs between different organs, suggesting a distinct partitioning of highly relevant FA. For the present study in cattle, a novel technology was applied to overcome rumen biohydrogenation of dietary unsaturated FA. Angus heifers were fed a straw-based diet supplemented for 8 weeks with 450 g/day of rumen-protected oil, either from fish (FO) or sunflower (SO). The FA composition in blood and five important organs, namely heart, kidney, liver, lung, and spleen, was examined. In blood, proportions of polyunsaturated FA were increased by supplementing FO compared to SO. The largest increase of eicosapentaenoic acid (EPA) proportion was found with FO instead of SO in the kidney, the lowest in the lung. Docosahexaenoic acid (DHA) was increased more in the liver than in kidney, lung, and spleen. The heart incorporated seven times more EPA than DHA, which is more than all other organs and described here for the first time in ruminants. In addition, the heart had the highest proportions of α-linolenic acid (18:3n-3) and linoleic acid (18:2n-6) of all organs. The proportions of polyunsaturated FA in the lung and spleen were exceptionally low compared to heart, liver, and kidney. In conclusion, it was shown that the response to FO in the distribution of dietary n-3 FA was organ-specific while proportions of n-6 FA were quite inert with respect to the type of oil supplemented.

Ferulic acid protects against methotrexate nephrotoxicityviaactivation of Nrf2/ARE/HO-1 signaling and PPARγ, and suppression of NF-κB/NLRP3 inflammasome axis

Ferulic acid prevents methotrexate-induced acute kidney injury by suppressing ROS/NF-κB/NLRP3 inflammasome axis, and activating PPARγ and Nrf2/ARE/HO-1 signaling.