Impact of L-Arginine on diabetes-induced neuropathy and myopathy: Roles of PAI-1, Irisin, oxidative stress, NF-κß, autophagy and microRNA-29a.

BACKGROUND: T2DM is a chronic disorder with progressive neuromuscular alterations. L-arginine (ARG) is the most common semi-essential amino acid having several metabolic functions. AIM: to investigate the impact of L-arginine in combating diabetic-induced neuromyopathy and its possible mechanisms. MATERIALS & METHODS: 24 rats were divided into CON, CON+ARG, DC, DC+ARG. Behavioral tests, Body weight (BW), fasting blood glucose (FBG), insulin, total antioxidant capacity (TAC), malondialdehyde (MDA), plasminogen activator inhibitor-1 (PAI-1), and irisin were done. Creatine kinase-MM (CK-MM), interleukin 4 (IL-4), interleukin 6 (IL-6), TAC, MDA, expression of microRNA-29a mRNA & light chain 3 protein were determined in muscle. Histological and NF-κß immunohistochemical expression in muscle and nerve were assessed. RESULTS: ARG supplementation to diabetic rats improved altered behavior, significantly increased BW, insulin, TAC, irisin and Il-4, decreased levels of glucose, microRNA-29a, NF-κß and LC3 expression, PAI-1, CK-MM and restored the normal histological appearance. CONCLUSIONS: ARG supplementation potently alleviated diabetic-induced neuromuscular alterations.

New Thiophenyl-pyrazolyl-thiazole Hybrids as DHFR Inhibitors: Design, Synthesis, Antimicrobial Evaluation, Molecular Modeling, and Biodistribution Studies.

The antibiotic resistance problems constitute a considerable threat to human health worldwide; thus, the discovery of new antimicrobial candidates to conquer this issue is an imperative requirement. From this view, new thiophenyl-pyrazolyl-thiazole hybrids 3-10 were synthesized and screened for their antibacterial efficiency versus Gram - and Gram + bacterial strains compared to the reference drug amoxicillin. It was noticed that the new hybrids displayed significant antibacterial efficacy versus Gram - bacteria, especially against Pseudomonas aeruginosa. Also, all the screened candidates demonstrated a noticeable antifungal effect against Candida albicans (MICs = 3.9-125 µg/mL) relative to fluconazole (MIC = 250 µg/mL). Moreover, the new hybrids were investigated for their antituberculosis potency against Mycobacterium tuberculosis (RCMB 010126). Derivatives 4c, 6b, 8b, 9b, and 10b demonstrated prominent antituberculosis efficiency (MICs = 0.12-1.95 µg/mL) compared with the reference drug isoniazid (MIC = 0.12 µg/mL). The latter derivatives were further assessed for their inhibitory potency versus M. tuberculosis DHFR enzyme. The compounds 4c, 6b and 10b presented a remarkable suppression effect with IC50 values of 4.21, 5.70, and 10.59 µM, respectively, compared to that of trimethoprim (IC50 = 6.23 µM). Furthermore, biodistribution profile using radiolabeling way revealed a perceived uptake of 131I-compound 6b into infection induced models. The docking study for the new hybrids 4c, 6b, 8b, 9b and 10b was performed to illustrate the various binding modes with Mtb DHFR enzyme. In silico ADMET studies for the most potent inhibitors 4c, 6b and 10b were also accomplished to predict their pharmacokinetic and physicochemical features.

Umbelliferone potentiates intestinal protective effect of Lactobacillus Acidophilus against methotrexate-induced intestinal injury: Biochemical and histological study.

Intestinal injury is a common adverse effect of methotrexate (MTX) therapy, limiting its clinical use. Despite oxidative stress and inflammation being the most embedded mechanism of injury, pharmacological agents that exhibit antioxidant and anti-inflammatory impacts could prevent such toxicities. This study aimed to assess the enteroprotective effect of lactobacillus acidophilus (LB) and/or umbelliferone (UMB) against MTX-induced intestinal injury. Histologically, pretreatment with LB, UMB, or their combinations preserve the intestinal histological structure and mucin content with superior effect in combination therapy. In addition, oral pretreatment with UMB, LB, or their combinations significantly restored oxidant/antioxidant status, as evidenced by the upregulation of Nrf2, SOD3, HO-1, GSH, and GST levels concurrent with a decline in MDA contents. Besides, they suppressed the inflammatory burden by inhibiting STAT3, MPO, TLR4, NF-κB, TNF-α, and IL-6 levels. Moreover, LB, UMB, or their combinations significantly upregulated Wnt and ß-catenin expression. Notably, pretreatment with the combination therapy is superior to monotherapy in protecting rats' small intestines from MTX-induced enteritis. In conclusion, combined pretreatment with LB and UMB could be a novel therapeutic regimen for conditions of intestinal injury induced by MTX via restoring oxidant/antioxidant balance and suppressing inflammatory burden.

Antioxidant, antiapoptotic, and antifibrotic abilities of L-Arginine ameliorate the testicular dysfunction in diabetic rats.

Testicular dysfunction and infertility are serious complications of diabetes mellitus (DM). L-Arginine (L-Arg) is a semi essential amino acid with various biological and metabolic functions. The molecular mechanisms of L-Arg on testicular dysfunction caused by DM remain elusive. This study aimed to assess the potential protective effect of L-Arg in diabetic testis and its possible mechanisms. 24 adult male Wistar albino rats were randomly divided into four groups: CON, L-Arg that received 1 g/kg body weight of L-Arg orally for 4 weeks, DM that fed a high fat diet followed by an injection of 30 mg/kg streptozotocin intraperitoneally, and L-Arg-treated DM that were diabetic and administered L-Arg. DM decreased relative testicular weight, reduced serum testosterone, and impaired semen parameters. Reduced total antioxidant capacity (TAC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px), in addition to increased transforming growth factor B1 (TGF-ß1) and nitric oxide (NO) levels, were found in the testicular tissue. This was associated with severe degenerative changes in the seminiferous tubules and interstitial cells of Leydig, reduction of Johnsen's score, significantly increased expression of both inducible nitric oxide synthase (iNOS) and caspase-3, and reduced zonula occludens (ZO)- 1 expression. Ultrastructurally, disrupted intercellular junctions and degeneration of interstitial cells of Leydig were observed. In contrast, treatment of diabetic animals with L-Arg increased TAC, SOD and GSH-Px, decreased TGF-ß1 and NO levels, downregulated iNOS and caspase-3 expression, upregulated ZO-1 expression, and maintained the integrity of the Sertoli cell junctions. Hence, L-Arg restored the normal testicular structure and function via its antioxidant, antiapoptotic, and antifibrotic effects.

Comparative Histological Study on the Effect of Tramadol Abuse on the Testis of Juvenile and Adult Male Albino Mice.

As a synthetic analog of codeine, tramadol is often prescribed to treat mild to moderate pains. This study was designed to estimate and compare the histological effect of tramadol on testes of both juvenile and adult male albino mice. A total number of 40 healthy male albino mice were classified into two main groups as follows: group I (juvenile group, includes 20 mice aged three weeks) subdivided equally into group Ia (control group received isotonic saline) and group Ib (tramadol-treated group received 40 mg/kg/d tramadol orally for 30 days); group II (adult group, includes 20 mice aged two months) subdivided equally into group IIa (control group received isotonic saline) and group IIb (tramadol-treated group). Juvenile and adult tramadol-treated groups showed numerous testicular changes, including blood vessels congestion, widening of intercellular spaces, vacuolization in interstitial tissues, luminal germ cells exfoliation, and increased expression of caspase-3 that indicated cellular apoptosis. In the ultrastructural examination, spermatogenic cells degenerated with the frequent appearance of apoptotic cells. Sertoli cells showed vacuolations, large lipid droplets, and disrupted intercellular cell junctions. These observed testicular changes were markedly observed in the juvenile group. Testicular abnormalities and apoptotic changes can be caused by tramadol administration. These abnormalities are more common in juvenile mice.

Can metformin modulate the retinal degenerative changes in a rat model of retinitis pigmentosa?

Retinitis pigmentosa (RP) affects over a million people worldwide, characterized by photoreceptor cell death, progressive retinal degeneration, and visual loss. Metformin is demonstrated as a potential therapeutic approach for preventing light-induced retinal degeneration by decreasing apoptosis and oxidative stress. This work aimed to investigate the effect of metformin on the retina of the N-Ethyl-N-nitrosourea (ENU) induced rat model of RP. Eighteen adult male Wistar rats were divided into two groups. Group I: normal vehicle control (N = 6). Group II: ENU-induced photoreceptor degeneration (N = 12) received a single intraperitoneal injection of ENU at a 600 mg/kg dose. Rats in group II were equally divided into two subgroups: IIa: photoreceptor degeneration-induced group and IIb: metformin-treated group (200 mg/kg) for seven days. Specimens from the retina were processed for light and electron microscopy. In ENU treated group, the retina revealed vacuolations and morphological changes in the glia (Müller cells and microglia) and blood capillaries. Increasing caspase-3 (apoptotic marker), iNOS (oxidative stress marker), CD68 (macrophage marker) and glial fibrillary acidic protein (GFAP) expression were detected. In the metformin-treated group, the retinal vacuolations reduced with the morphological improvement in the glia and blood capillaries. Caspase-3, iNOS, CD68, and GFAP expression decreased. Metformin was found to have a neuroprotective effect on the retina in ENU induced rat model of RP.

Ameliorative role of alpha-lipoic acid in renal cortical structural damage, induced by limb ischemia-reperfusion injury in the rat.

Ischemia-reperfusion injury is related to kidney dysfunction due to bilateral lower limb ischemia. This kidney injury may lead to acute kidney failure and mortality. Alpha-Lipoic Acid, a known antioxidant, can ameliorate kidney dysfunction and histopathology related to several etiologies. Ischemia was performed in adult male rats by bilateral femoral artery occlusion, then ischemia-reperfusion was done for 1 day and 7 days. Lipoic acid was administered to rats that had undergone ischemia-reperfusion for 7 days. The renal cortices of the kidneys of the tested groups were processed for light and electron microscopic examination. Immunohistochemical evaluation was performed using the following markers: cleaved caspase 3, inducible nitric oxide synthase, and tumor necrosis factor-alpha. There was damage to the renal cortical tubules and degeneration of podocytes and thickening of the glomerular basement membrane. Additionally, there was an increase in apoptosis and the inflammatory markers' immunoreactivity. Administration of alpha-lipoic acid resulted in improvement of the structural and immunohistochemical changes of the renal cortex. This may suggest a therapeutic rule of it and promising application for variable kidney injuries.

Metformin treatment confers protection of the optic nerve following photoreceptor degeneration.

Acquired or inherited or photoreceptor loss causes retinal ganglion cell loss and ultimately axonal transport alteration. Thus, therapies should be applied early during photoreceptors degeneration before the remodeling process reaches the inner retina. This study aimed to evaluate the protective effect of metformin on the rat optic nerve following photoreceptors loss induced by N-Ethyl-N-nitrosourea (ENU). Eighteen adults male Wistar rats were divided into two groups. Group I: normal vehicle control (n=6). Group II: ENU-induced photoreceptors degeneration (n=12) received a single intraperitoneal injection of ENU at a dose of 600 mg/kg. Rats in group II were equally divided into two subgroups: IIa: photoreceptor degeneration induced group and IIb: metformin treated group (200 mg/kg) for 7 days. Specimens from the optic nerve were processed for light and electron microscopy. In ENU treated group, the optic nerve revealed reduction in the diameter of the optic nerve fibers and thinning of myelin sheath with morphological changes in the glia (astrocytes, oligodendrocytes, and microglia). Caspase-3 (apoptotic marker), iNOS (oxidative stress marker) and CD68 (macrophage marker) expression increased. In metformin-treated group, the diameter of optic nerve fibers and myelin sheath thickness increased with improvement of the deterioration in the glia. Caspase-3, iNOS and CD68 expression decreased. Metformin ameliorates the histological changes of the rat optic nerve following photoreceptors loss induced by ENU.

Pioglitazone and/or irbesartan ameliorate COPD-induced endothelial dysfunction in side stream cigarette smoke-exposed mice model.

AIMS: Cigarette smoking (CS) is the main cause of chronic obstructive pulmonary disease (COPD). Endothelial dysfunction is related to the severity of pulmonary disease in COPD. This study aimed to evaluate the effectiveness of single and combined administration of pioglitazone (Pio) and irbesartan (Irb) against COPD-induced endothelial dysfunction in mice and the involvement of NO and H2S in their effects. MATERIALS AND METHODS: Adult male Swiss mice (n = 40, weighing 25-30 g) were assigned into 5 groups. The normal control group received 1% carboxy methyl cellulose (CMC). The CS group was exposed to CS and administered 1% CMC for 3 months. The CS + Pio, CS + Irb, and CS + Pio/Irb groups were subjected to CS and received Pio (60 mg/kg), Irb (50 mg/kg), and their combination respectively, daily orally for 3 months. Body weight gain, mean blood pressure, urinary albumin, serum NO and ET-1 levels with TNF-α and IL-2 levels in lung tissue and bronchoalveolar lavage were measured. Lung H2S and ET-1 levels, protein expression of PPARγ in lung and VEGF in lung and aortic tissues with histological changes were assessed. KEY FINDINGS: Our results illustrated that CS induced a model of COPD with endothelial dysfunction in mice. Pio/Irb singly and in combination elicited protective effects against the pathophysiology of the disease with more improvement in the combined group. There is a strong correlation between NO and H2S as well as the other measured parameters. SIGNIFICANCE: Collectively, both drugs performed these effects via their anti-inflammatory potential and increasing H2S and NO levels.

Enhancing Tumor Targeting Efficiency of Radiolabeled Uridine (via) Incorporation into Nanocubosomal Dispersions.

Background: Several nanosystems are currently being utilized to enhance the targeting efficiency of several cancer chemotherapeutic agents. This study was designed to improve tumor accumulation of iodine-125 (125I)-uridine via incorporation into a nanocubosomal preparation. Materials and Methods: Nanocubosomes were prepared with the aid of Glycerol mono-oleate and Pluronic F127. Each prepared nanocubosomal preparation was adequately characterized by testing their particle size, polydispersity index (PDI), ζ potential (ZP), and transmission electron microscopy. The radiolabeling of uridine with 125I was attempted using several oxidizing agents to achieve a high radiochemical yield, and the factors affecting the reaction yield were studied in detail. A comparative biodistribution study of free 125I-uridine and 125I-uridine loaded nanocubosomes was performed in normal and tumor bearing mice. The biodistribution was evaluated by intravenous injection of the sterile test solution, and animals were anesthetized and dissected at different time intervals postinjection (p.i.). Results: 125I-uridine was obtained in a high radiochemical yield (92.5% ± 0.8%). Afterward, 125I uridine was incorporated in a selected nanocubosome formulation, which showed nanosized cubic particles (178.6 ± 0.90 nm) with PDI (0.301 ± 0.04) and a ZP (34.35 ± 0.4). The biodistribution studies revealed that 125I-uridine nanocubosomes showed higher tumor localization (3.1 ± 0.4%IA/g at 2 h p.i. and a tumor/muscle ratio of 6.2) compared with the free 125I-uridine (2.7% ± 0.4%IA/g at 2 h p.i. and a tumor/muscle ratio of 3.3). Conclusion: The results of this study confirmed that 125I-uridine loaded nanocubosome had better efficiency in targeting the tumor site, which makes it an adequate targeting agent for tumor imaging.

Nicotine-induced oxidative stress alters sciatic nerve barriers in rat through modulation of ZO-1 & VEGF expression.

This study aimed to evaluate the histopathological and ultrastructural changes in sciatic nerve barriers after exposure to different doses of nicotine. Twenty-seven adult male rats were divided into 2 groups; group I served as control (n = 9) and group II that received nicotine (n = 18) was subdivided into two equal subgroups; group IIa and group IIb that were injected subcutaneously daily for one month with nicotine at a dose of 3 mg/kg and 6 mg/kg body weight, respectively. Specimens of sciatic nerve were processed for light and electron microscopy. Immunohistochemical expression of ZO-1 and vascular endothelium growth factor (VEGF) were investigated. Abundance of mRNA for VEGF was determined via qRT-PCR. Total antioxidant capacity (TAC), malondialdehyde (MDA), alanine transaminase (ALT) and aspartate transaminase (AST) were measured. Group IIb showed increased perineural fibrosis and myelin abnormalities. ZO-1 expression was significantly decreased. Schwann cells showed features of apoptosis and blood capillaries showed disrupted lining. High statistical difference in the level of mRNA expression of VEGF between group IIb and group I was found. There was decreased level of TAC and increased MDA, ALT and AST. A dose-dependent nicotine-induced oxidative stress on the sciatic nerve occurred via disruption of nerve barriers, altered VEGF and ZO-1 levels.

The effect of omega-3 on cognition in hypothyroid adult male rats.

Thyroid hormones and omega-3 are essential for normal brain functions. Recent studies have suggested that omega-3 may protect against the risk of dementia. The aim of this study was to investigate the effect of hypothyroidism on spatial learning and memory in adult male rats, the underlying mechanisms and the possible therapeutic value of omega-3 supplementation. Thirty male rats were divided into three groups; control, hypothyroid and omega-3 treated. Hypothyroidism induced significant deficits in working and reference memories in radial arm maze, retention deficits in passive avoidance test and impaired intermediate and long-term memories in novel object recognition test. Serum total antioxidant capacity (TAC) and hippocampal serotonin and γ-aminobutyric acid (GABA) levels were decreased in the hypothyroid group as compared to the control group. Moreover, the hippocampus of hypothyroid rats showed marked structural changes as diffuse vacuolar degeneration and distortion of the pyramidal cells. Immunohistochemistry showed that the expression of Cav1.2 (the voltage dependent LTCC alpha 1c subunit) protein was increased in the hypothyroid group as compared to the control group. Omega-3 supplementation ameliorated memory deficits, increased TAC, decreased the structural changes and decreased the expression of Cav1.2 protein. In conclusion omega-3 could be useful as a neuroprotective agent against hypothyroidism-induced cognitive impairment.

Protective effects of thymoquinone and l-cysteine on cadmium-induced reproductive toxicity in rats.

This study was conducted to investigate the possible protective role of thymoquinone (TQ) and l-cysteine on the reproductive toxicity of male rats induced by cadmium chloride (CdCl2). Forty rats were divided into four even groups. The first group served as untreated control. The second, third and fourth groups received CdCl2, CdCl2 and TQ, and CdCl2 and l-cysteine, respectively for 56 days. Cd exposure caused spermatological damage (decrease sperm count and motility and increased the rates of sperm abnormalities), decrease serum testosterone level and increased oxidative stress. Histological alterations were also observed in the form of vascular and cellular changes in CdCl2 treated rats. The vascular changes were congestion of the blood vessels with interstitial edema in the testes, epididymis, seminal vesicle and prostate. The cellular changes were in the form of degenerative changes with presence of multinucleated giant cells in the lumen of seminiferous tubules, vacuolation and sloughing of the lining epithelium of the epididymis, seminal vesiculitis and prostatitis. Co-administration of TQ and l-cysteine with CdCl2 increased glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and testosterone and reduced lipid peroxidation (LPO) activity. In conclusion, our results showed that TQ and l-cysteine can ameliorate the deleterious effects of CdCl2 probably by activating testicular endocrine and antioxidant systems.