Antidiabetic drug sitagliptin blocks cyclophosphamide cerebral neurotoxicity by activating Nrf2 and suppressing redox cycle imbalance, inflammatory iNOS/NO/NF-κB response and caspase-3/Bax activation in rats

Coenzyme Q10 ameliorates cyclophosphamide-induced chemobrain by repressing neuronal apoptosis and preserving hippocampal neurogenesis: Mechanistic roles of Wnt/ β-catenin signaling pathway

Deterioration in the neurocognitive function of cancer patients referred to as "Chemobrain" is a devastating obstacle associated with cyclophosphamide (CYP). CYP is an alkylating agent, clinically utilized as an efficient anticancer and immunosuppressant. Coenzyme Q10 (CoQ10) is a worthwhile micronutrient with diverse biological activities embracing antioxidant, anti-apoptotic, and neuroprotective effects. The current experiment was designed for investigating the neuroprotective capability of CoQ10 versus CYP-elicited chemobrain in rats besides elucidating the causal molecular mechanisms. Male Sprague Dawley rats received CoQ10 (10 mg/kg, orally, once daily, for 10 days) and/or a single dose of CYP (200 mg/kg i.p. on day 7). CoQ10 counteracted CYP-induced cognitive and motor dysfunction as demonstrated by the findings of neurobehavioral tests (passive avoidance, Y maze, locomotion, and rotarod tests). Histopathological analysis further affirmed the neuroprotective abilities of CoQ10. CoQ10 effectually diminished CYP-provoked oxidative injury by restoring the antioxidant activity of catalase (CAT) enzyme while reducing malondialdehyde (MDA) levels. Besides, CoQ10 efficiently repressed CYP-induced neuronal apoptosis by downregulating the expression of Bax and caspase-3 while upregulating the Bcl-2 expression. Moreover, CoQ10 hampered CYP-provoked upregulation in acetylcholinesterase (AChE) activity. Furthermore, CoQ10 considerably augmented hippocampal neurogenesis by elevating the expressions of brain-derived neurotrophic factor (BDNF) and Ki-67. These promising neuroprotective effects can be credited to upregulating Wnt/β-catenin pathway as evidenced by the elevated expressions of Wnt-3a, β-catenin, and Phoshpo-glycogen synthase kinase-3 β (p-GSK-3β). Collectively, these findings proved the neuroprotective capabilities of CoQ10 against CYP-induced chemobrain through combating oxidative injury, repressing intrinsic apoptosis, boosting neurogenesis, and eventually upregulating the Wnt/β-catenin pathway.

Thymoquinone Abrogates Acrylamide-Induced Cerebellar Toxicity via Modulation of Nuclear Factor Erythroid 2-Related Factor 2/Nuclear Factor Kappa B Signaling, Oxidative Neuroinflammation, and Neuroapoptosis in Rats

Acrylamide (ACR) is an obligate human neurotoxicant ubiquitously produced and found in foods processed at high temperature. There is an increasing public health concern regarding its probable carcinogenic potential. Its prevailing toxicity mechanism is oxidative inflammation and apoptosis. Herein, we explored whether thymoquinone (TQ), a bioactive quinone in Nigella sativa seed, could mitigate ACR-induced cerebellar toxicity in rats. Our study design featured four rat groups: control, TQ (5 mg/kg bw), ACR (50 mg/kg bw), and TQ + ACR (5 mg/kg + 50 mg/kg). After 14 days of respective treatments, cerebellar homogenate was used to estimate acetylcholinesterase activity (AchE) activity, antioxidant enzymes (catalase [CAT], superoxide dismutase [SOD], and glutathione peroxidase [GPx]), malondialdehyde (MDA), inflammatory cytokines (interleukin [IL]-6, tumor necrosis factor [TNF]-α, IL-4, and IL-10), nuclear factor kappa B (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), caspase-3, and caspase-9. The level of DNA damage by fragmentation and histopathological lesions was also determined in the cerebellum. The rat exposure to ACR caused significant decreases in the cerebellar activities of AchE, CAT, SOD, and GPx, IL-4, IL-10, and expression of Nrf2, whereas the levels of MDA, IL-6, TNF-α, caspase-3, and caspase-9 were prominently increased compared with the control. ACR induced significant DNA fragments and cerebellar lesions when compared with the control. Contrarily, TQ treatment inhibited the depression of CAT, SOD, and GPx activities and reversed the MDA level and expression of Nrf2/NF-κB, cytokines, and caspases. These effects were confirmed by reduced DNA damage and cerebellar histopathological lesions in comparison with the ACR. TQ afforded neuroprotection via its antioxidant, anti-inflammatory, and antiapoptotic mechanisms in rats.

Epicatechin ameliorates glucose intolerance and hepatotoxicity in sodium arsenite-treated mice

Arsenic is a metalloid found in the environment that causes toxic effects in different organs, mainly the liver. This study aimed to investigate the protective effects of epicatechin (EC), a natural flavonol, on glucose intolerance (GI) and liver toxicity caused by sodium arsenite (SA) in mice. Our findings showed that SA exposure led to the development of GI. Liver tissue damage and decreased pancreatic Langerhans islet size were also observed in this study. Mice exposed to SA exhibited hepatic oxidative damage, indicated by reduced antioxidant markers (such as superoxide dismutase, catalase, glutathione peroxidase, and glutathione), along with elevated levels of thiobarbituric acid reactive substances. SA administration elevated the serum activities of liver enzymes alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. Furthermore, notable increases in the levels of inflammatory and apoptotic markers (Toll-like receptor 4, nuclear factor-kappa B, tumor necrosis factor-α, nitric oxide, B-cell lymphoma-2, and cysteine aspartate-specific protease-3) were observed in the liver. Treatment of SA-exposed mice with EC considerably reversed these biochemical and histological changes. This study demonstrated the beneficial effects of EC in ameliorating SA-induced hyperglycemia and hepatotoxicity due to its ability to enhance the antioxidant system by modulating inflammation and apoptosis.

New Insights into the Pleiotropic Actions of Dipeptidyl Peptidase-4 Inhibitors Beyond Glycaemic Control

Dipeptidyl peptidase-4 (DPP-4) is a multifunctional serine ectopeptidase that cleaves and modifies a plethora of substrates, including regulatory peptides, cytokines and chemokines. DPP-4 is implicated in the regulation of immune response, viral entry, cellular adhesion, metastasis and chemotaxis. Regarding its numerous substrates and extensive expression inside the body, multitasking DPP-4 has been assumed to participate in different pathophysiological mechanisms. DPP-4 inhibitors or gliptins are increasingly used for the treatment of type 2 diabetes mellitus. Several reports from experimental and clinical studies have clarified that DPP-4 inhibitors exert many beneficial pleiotropic effects beyond glycaemic control, which are mediated by anti-inflammatory, anti-oxidant, anti-fibrotic and anti-apoptotic actions. The present review will highlight the most recent findings in the literature about these pleiotropic effects and the potential mechanisms underlying these benefits, with a specific focus on the potential effectiveness of DPP-4 inhibitors in coronavirus disease-19 and diabetic kidney disease.

Trace elements and metal nanoparticles: mechanistic approaches to mitigating chemotherapy-induced toxicity-a review of literature evidence

Anticancer chemotherapy (ACT) remains a cornerstone in cancer treatment, despite significant advances in pharmacology over recent decades. However, its associated side effect toxicity continues to pose a major concern for both oncology clinicians and patients, significantly impacting treatment protocols and patient quality of life. Current clinical strategies to mitigate ACT-induced toxicity have proven largely unsatisfactory, leaving a critical unmet need to block toxicity mechanisms without diminishing ACT's therapeutic efficacy. This review aims to document the molecular mechanisms underlying ACT toxicity and highlight research efforts exploring the protective effects of trace elements (TEs) and their nanoparticles (NPs) against these mechanisms. Our literature review reveals that the primary driver of ACT toxicity is redox imbalance, which triggers oxidative inflammation, apoptosis, endoplasmic reticulum stress, mitochondrial dysfunction, autophagy, and dysregulation of signaling pathways such as PI3K/mTOR/Akt. Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective signaling pathways like Sirt1/PPAR-γ/PGC-1α/FOXO-3 and Nrf2/HO-1/ARE. However, evidence regarding the roles of lncRNA and the Wnt/β-catenin pathway in ACT toxicity remains inconsistent, and the impact of TEs and NPs on ACT efficacy is not fully understood. Further research is needed to confirm the protective effects of TEs and their NPs against ACT toxicity in cancer patients. In summary, TEs and their NPs present a promising avenue as adjuvant agents for preventing non-target organ toxicity induced by ACT.

LC-qTOF-MS/MS phytochemical profiling of Tabebuia impetiginosa (Mart. Ex DC.) Standl. leaf and assessment of its neuroprotective potential in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Tabebuia impetiginosa (Bignoniaceae) was traditionally used for memory enhancement and central nervous system (CNS) stimulation.

AIM OF THE STUDY

This study aims to create a metabolic profile of the ethyl acetate fraction of T. impetiginosa (TEF) and investigate for the first time its neuroprotective potential on cyclophosphamide (CP)-induced chemobrain, validating its traditional use.

MATERIALS AND METHODS

Metabolite profiling of TEF was performed using Liquid Chromatography coupled with Quadrupole Time of Flight-Mass/Mass Spectrometry (LC-qTOF-MS/MS). For the in vivo study, CP (200 mg/kg, i.p.) was administered to induce cognitive impairment in rats; TEF (30 mg/kg, p.o.) was administered throughout the 14 days of the experiment to assess its role in mitigating CP-induced neuronal deficits. Behavioral tests including locomotor, Y-maze, and passive avoidance tests were conducted. Additionally, biochemical markers such as reduced glutathione (GSH), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), and caspase-3 immunoexpression were assessed in the hippocampus area.

RESULTS

Forty-four phytoconstituents were tentatively identified in TEF, mainly iridoids and organic acids. TEF showed significant memory enhancement as evidenced by the increase in step-through latency in the passive avoidance test by 1.5 folds and the increase in sequence alternation percentage (SAP) in the Y-maze test by 67.3%, as compared to CP-group. Moreover, it showed pronounced antioxidant and anti-inflammatory potentials evidenced by the significant elevation in reduced glutathione (GSH) levels by 80% and a pronounced decline in MDA and TNF-α levels by 24% and 45%, respectively relative to the CP group. TEF treatment restored normal hippocampal histological features and attenuated apoptotic caspase-3 expression by 70% compared to the CP group.

CONCLUSIONS

TEF can act as a promising natural scaffold in managing the chemobrain induced by CP in cancer patients.

Targeting SIRT1/AMPK/Nrf2/NF-кB by sitagliptin protects against oxidative stress-mediated ER stress and inflammation during ANIT-induced cholestatic liver injury

Intrahepatic cholestasis is a common clinical form of hepatobiliary injury characterized by the intrahepatic accumulation of toxic bile acids. Besides its antidiabetic activity, the dipeptidyl peptidase IV inhibitor sitagliptin (SG) has been recently assigned diverse pharmacological activities and therapeutic potential against different disorders owing to its emerging antioxidant and anti-inflammatory properties. The current study explored the potential hepatoprotective effect of SG on α-naphthyl isothiocyanate (ANIT)-induced cholestatic liver injury (CLI) in mice and investigate its possible targeted signaling pathways. Mice received SG (10 and 20 mg/kg) for four consecutive days, two days before and after a single oral administration of ANIT (75 mg/kg). Our results revealed that SG administration remarkably prevented ANIT-induced histopathological lesions in the liver and maintained hepatic functions and oxidative/antioxidant balance. Ultimately, SG counteracted the inflammatory response in the liver, as indicated by the marked suppression of hepatic expression of NF-κB, TNF-α, and IL-6. Moreover, it inhibited the endoplasmic reticulum (ER) stress response in the liver. These beneficial effects of SG were accompanied by upregulation of SIRT1, p-AMPK, and Nrf2 expressions while downregulating keap1 expression in the liver. In conclusion, this study is the first to demonstrate the ability of SG to protect against ANIT-induced CLI through modulating multiple signaling cascades, including SIRT1/AMPK, Nrf2/keap1, and NF-кB, which resulted in enhanced antioxidant capacity and repressed inflammatory and ER stress responses in the liver.

Molecular mechanisms underlying cyclophosphamide-induced cognitive impairment and strategies for neuroprotection in preclinical models

Cyclophosphamide has drastically enhanced the expectancy and quality of life of cancer patients. However, it is accompanied by diverse neurological complications which are considered a dose-limiting adverse effect. Neurotoxicity caused by cyclophosphamide can manifest in numerous manners including anxiety, depression, motor dysfunction and cognitive deficits. This review article offers an overview on cyclophosphamide-induced neurotoxicity, providing a unified point of view on the possible underlying molecular mechanisms including oxidative brain damage, neuroinflammation, apoptotic neuronal cell death as well as disruption of the balance of brain neurotransmitters and neurotrophic factors. Besides, this review sheds light on the promising protective agents that have been investigated using preclinical animal models as well as their biological targets and protection mechanisms. Despite promising results in experimental models, none of these agents has been studied in clinical trials. Thus, there is lack of evidence to advocate the use of any neuroprotective agent in the clinical setting. Furthermore, none of the protective agents has been evaluated for its effect on the anticancer activity of cyclophosphamide in tumor-bearing animals. Therefore, there is a great necessity for adequate well-designed clinical studies for evaluation of the therapeutic values of these candidates. Conclusively, this review summarizes the molecular mechanisms accounting for cyclophosphamide-induced neurotoxicity together with the potential protective strategies seeking for downgrading this neurological complication, thus enhancing the quality of life and well-being of cancer patients treated with cyclophosphamide.

Irbesartan mitigates the impact of cyclophosphamide-induced acute neurotoxicity in rats: Shedding highlights on NLRP3 inflammasome/CASP-1 pathway-driven immunomodulation

IIrbesartan (IRB), an angiotensin II type 1 receptor (AT1R) antagonist, has been widely employed in the medical field for its effectiveness in managing hypertension. However, there have been no documented investigations regarding the immunostimulatory properties of IRB. To address this gap, this study has been performed to assess the neuroprotective impact of IRB as an immunostimulatory agent in mitigating acute neurotoxicity induced by cyclophosphamide (CYP) in rats. mRNA levels of nuclear factor erythroid 2 (Nrf-2), interleukin (IL)-18, IL-1β, and MMP-1 have been assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the levels of malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) has been evaluated to assess the oxidative stress. Additionally, macrophage inflammatory protein 2 (MIP2) has been evaluated using enzyme-linked immunosorbent assay (ELISA). Western blotting has been used to investigate the protein expression of nucleotide binding oligomerization domain-like receptor protein 3 (NLRP3) and caspase-1 (CASP-1), along with an assessment of histopathological changes. Administration of IRB protected against oxidative stress by augmenting the levels of GSH and SOD as well as reducing MDA level. Also, administration of IRB led to a diminishment in the brain levels of MIP2 and MMP1. Furthermore, it led to a suppression of IL-1β and IL-18 levels, which are correlated with a reduction in the abundance of NLRP3 and subsequently CASP-1. This study provides new insights into the immunomodulatory effects of IRB in the context of CYP-induced acute neurotoxicity. Specifically, IRB exerts its effects by reducing oxidative stress, neuroinflammation, inhibiting chemokine recruitment, and mitigating neuronal degeneration through the modulation of immune markers. Therefore, it can be inferred that the use of IRB as an immunomodulator has the potential to effectively mitigate immune disorders associated with inflammation.

Geraniol prevents CCl4-induced hepatotoxicity via suppression of hepatic oxidative stress, pro-inflammation and apoptosis in rats

Carbon tetrachloride (CCl4) is a classic chemical hepatotoxicant that triggers liver damage through hepatic exacerbation of oxidative stress. Geraniol (GRL) is a natural bioactive acyclic monoterpene with several pharmacological effects. We thus explored whether GRL could prevent CCl4-triggered hepatic toxicity. Rats were divided and administered GRL (100 mg/kg) and/or CCl4 (1 ml/kg of 1:1 v/v CCl4: olive oil) in Control group, GRL group, CCl4 group, GRL + CCl4 groups 2 times per week for 4 consecutive weeks. CCl4 caused significantly (p < 0.05) elevated serum activities of alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total bilirubin (TB), whereas the albumin (ALB) and total protein (TP) levels were significantly (p < 0.05) reduced relative to the control group. The liver activities of catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD) decreased significantly (p < 0.05), while malondialdehyde (MDA) level evidently elevated in comparison to the control group. The CCl4 exposure caused significant increases in proinflammatory interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), apoptotic caspase-3 and caspase-9 levels, whereas the anti-inflammatory interleukin-4 (IL-4) and interleukin-10 (IL-10) were reduced in consistent with histopathological changes compared to the control. On the contrary, the GRL administration prevented the hepatic toxicity and lesions through restoration of liver status markers, antioxidant enzyme activities, MDA, cytokines and apoptosis in comparison to the CCl4 group. Altogether, the findings reveal that GRL could abrogate CCl4-provoked hepatic toxicity via inhibition of hepatic oxidative stress, inflammation and apoptosis in rats.

Impacts of inflammatory cytokines on depression: a cohort study

BACKGROUND

Inflammatory factors are associated with depression. We seek to investigate the correlation between inflammatory cytokines and prognosis of depression or suicidal ideation and behavior at 3 months in depression patients.

METHODS

Eighty-two depressed outpatients were recruited and treated as usual. Plasma cytokines were measured at baseline. Patients were followed up with Patient Health Questionnaire-9 and suicidal ideation and behavior according to the item 3 of Hamilton depression scale for 3 months.

RESULTS

Compared to the depression patients with low level of interleukin-1β, the high one had severe depressive symptoms at month 2 and 3 (B 0.92, P < 0.01; B 0.86, P = 0.02; respectively). The incidence of suicidal ideation or behavior was 18.3% at 3 months. Depression patients with high levels of tumor necrosis factor-α showed high risk of suicidal ideation and behavior than the low one (OR 2.16, 95% CI 1.00-4.65, P = 0.04).

CONCLUSIONS

High levels of interleukin-1β and tumor necrosis factor-α were predictive of middle-term severe depressive symptoms and suicidal ideation and behavior respectively.

Ultrasound-assisted hydrogen peroxide-ascorbic acid method to degrade sweet corncob polysaccharides can help treat type 2 diabetes via multiple pathways in vivo

In this study, we aimed to investigate the impact of various ultrasound durations on the structure and bioactivity of sweet corncob polysaccharides treated with ultrasound-assisted degradation using hydrogen peroxide and ascorbic acid (H2O2-Vc). We subjected sweet corncob polysaccharides to ultrasound treatment for 0, 30, 60, and 90 min alongside the H2O2-Vc method. We then analyzed their chemical composition and structure. Additionally, we administered these polysaccharides to mice with type 2 diabetes (T2DM) through gavage at a dosage of 200 mg/kg/day. The results indicated a significant reduction in the molecular weight of the degraded sweet corncob polysaccharides, while their composition remained relatively stable. However, the basic structure of the polysaccharides was retained. In vivo experiments demonstrated that ultrasound-assisted degradation of these polysaccharides had a positive impact on T2DM, particularly the 60-minute ultrasound treatment (UH-DSCBP-60 min), which effectively controlled blood glucose levels by regulating glycolipid metabolism in the livers of mice with T2DM. This approach also reduced inflammation and oxidative stress levels and inhibited disaccharide activity in the small intestine. We demonstrated that ultrasound can positively affect the sweet corncob polysaccharides hypoglycemic activity. The findings of our study provide a theoretical foundation for the valuable utilization of sweet corncob polysaccharides.