Exploring the possible mechanism involved in the anti-nociceptive effect of ß-sitosterol: modulation of oxidative stress, nitric oxide and IL-6.

Β-sitosterol is a phytosterol, documented to possess various activities including protection against inflammation, diabetes and Alzheimer's disease. The current investigation was designed to explore the analgesic potential of ß-sitosterol and the possible molecular mechanism involved in the observed effect. ß-sitosterol was administered at varying doses of 10, 20, and 40 mg/kg before subjecting the mice to acetic acid and formalin challenges. The number of writhings in acetic acid and the number of flinchings and foot tappings were quantified in the formalin test. For mechanistic studies, substance P (cyclooxygenase-2 (COX-2) stimulator) and L-Nitro arginine methyl ester (L-NAME) (nitric oxide synthetases (NOS) inhibitor) and L-arginine (nitric oxide precursor) were administered before ß-sitosterol treatment. ß-sitosterol (10, 20, 40 mg/kg) treatment significantly reduced acetic acid-induced writhings and ameliorated the formalin-induced inflammatory phase dose-dependently. Whereas, 40 mg/kg dose of ß-sitosterol abrogated the formalin-induced neurogenic phase. Substance-P abrogated the effect of ß-sitosterol in both neurogenic and inflammatory phases. Whereas, L-arginine only abrogated the inflammatory phase. In biochemical analysis, ß-sitosterol treatment reduced the level of interleukin-6 (IL-6), thiobarbituric acid reactive substances (TBARS) and increased the level of reduced glutathione (GSH). Furthermore, L-arginine and substance-P abrogated the GSH increasing and TBARS lowering effect of ß-sitosterol (40 mg/kg). Overall, the current study delineated that ß-sitosterol may induce an anti-nociceptive effect via inhibiting the IL-6, oxidative stress, cyclo-oxygenase and nitric oxide.

Understanding the phytochemistry and molecular insights to the pharmacology of Angelica archangelica L. (garden angelica) and its bioactive components.

Plant-derived molecules have enduring usefulness in treating diseases, and herbal drugs have emerged as a vital component of global therapeutic demand. Angelica archangelica L. (A. archangelica), commonly known as garden angelica, is an aromatic food plant used in culinary procedures as a flavoring agent. In the traditional medicine system, it is regarded as an "Angel plant" due to its miraculous curative power. This review aims to provide a comprehensive summary of the plant's taxonomic profile, ethnopharmacology, Phytochemistry, and pharmacological activities. Various in vivo and in vitro experiments have validated that the plant possesses broad pharmacological potential. The biological activities attributed to the plant include anti-anxiety activity, anti-convulsant activity, cognition enhancer, antiviral activity, cholinesterase inhibitory potential, antiinflammatory activity, gastroprotective activity, and radioprotective activity. The beneficial effects of the plant are credited to its bioactive components, that is, coumarins and volatile oils. The review summarizes the pharmacological activities of crude extract and its bioactive fractions and has also explored their target-oriented effects. This review will be of value in undertaking further investigations on the plant with regard to exploring mechanism-based pharmacological approaches on A. archangelica.

Daphnetin, a natural coumarin averts reserpine-induced fibromyalgia in mice: modulation of MAO-A.

Fibromyalgia is a common, chronic, and generalized pain syndrome that is often associated with comorbid depression. The etiology of fibromyalgia is complex; most researchers have documented that the hallmark symptoms are due to the central nervous system's abnormal functioning. Neurotransmitters such as serotonin, norepinephrine, and glutamate, have been reported to be key regulators of fibromyalgia syndrome. Daphnetin is a 7, 8 dihydroxy coumarin widely distributed in Thymelaeaceae family plants, possessing various activities such as anti-arthritic, anti-tumor, anti-malarial, and anti-parasitic. The present study was designed to explore the potential of daphnetin against reserpine-induced fibromyalgia in mice. In mice, a fibromyalgia-like state was achieved by injecting reserpine (0.5 mg/kg, s.c) continuously for 3 days. All behavioral tests were conducted on the 4th and 6th day of experimentation. Reserpine administration significantly increased the mechanical hypersensitivity in electronic von Frey (eVF) and pressure application measurement (PAM) tests. It also increased the immobility period and time to reach the platform in force swim test (FST) and Morris water maze (MWM) test, respectively. In the biochemical analysis, reserpine treatment upregulated the monoamine oxidase-A (MAO-A) activity and level of glutamate, tumor necrosis factor-alpha (TNF-α), interleukin-1beta (IL-1ß), and thiobarbituric acid reactive substances (TBARS). Whereas, it decreased the level of glutathione (GSH), dopamine, serotonin, and norepinephrine. Daphnetin pretreatment attenuated the behavioral and biochemical changes induced by reserpine. Thus, the current investigation results delineate that daphnetin might exert its protective effect by inhibiting inflammatory stress and MAO-A-mediated neurotransmitter depletion and oxidative stress.

Involvement of Oxidative Stress and Nerve Growth Factor in Behavioral and Biochemical Deficits of Experimentally Induced Musculoskeletal Pain in Mice: Ameliorative Effects of Heraclin.

Musculoskeletal pain is a widespread complex regional pain syndrome associated with altered emotional and cognitive functioning along with heightened physical disability that has become a global health concern. Effective management of this disorder and associated disabilities includes accurate diagnosis of its biomarkers and instituting mechanism-based therapeutic interventions. Herein, we explored the role of heraclin, a plant-derived molecule, in musculoskeletal pain and its underlying mechanistic approaches in an experimental mouse model. Reserpine (0.5 mg/kg) for 3 consecutive days evoked hyperalgesia, motor incoordination, lack of exploratory behavior, anxiety, and cognition lapse in mice. Reserpine-challenged mice displayed higher serum cytokine level, altered brain neurotransmitter content, elevated brain and muscle oxidative stress, and upregulated brain nerve growth factor receptor expression. Treatment with heraclin (10 mg/kg for 5 consecutive days) exerted analgesic effect and improved motor coordination and memory deficits in mice. Heraclin arrested serum cytokine rise, normalized brain neurotransmitter content, reduced tissue oxidative stress, and downregulated the nerve growth factor receptor expression. Therefore, it may be suggested that heraclin exerts beneficial effects against reserpine-induced musculoskeletal pain disorder possibly through the attenuation of NGFR-mediated pain and inflammatory signaling. Graphical Abstract.

Skimmetin/osthole mitigates pain-depression dyad via inhibiting inflammatory and oxidative stress-mediated neurotransmitter dysregulation.

Pain and depression are often co-existing pathological states that promote mutual severity resulting in limited efficacy of current treatment strategies. Thus, there is a need to develop an efficacious alternate treatment regimen for pain-depression dyad. Skimmetin and osthole are molecules of natural origin that have been explored for an anti-hyperglycemic, anti-bacterial, anti-fungal, and anti-diabetic activities in preclinical studies. in animal models. The current study has been designed to explore the beneficial effect of skimmetin/osthole in reserpine-induced pain-depression dyad in mice. Female Swiss albino mice (n = 6) were challenged with reserpine (0.5 mg/kg s.c.) for the first 3 days to induce a pain-depression dyad-like state. Skimmetin (10 mg/kg i.p.) and osthole (10 mg/kg i.p.) were administered for 5 days consecutively, starting from the first day of study. Reserpine treatment significantly reduced the pain threshold in the pressure application measurement (PAM) and electronic von frey (eVF) test. In forced swim test (FST) and Morris water maze (MWM) test mice displayed an increased immobility time and latency to reach platform respectively. Biochemical results showed an increased level of TNF-α, IL-1ß, TBARS, glutamate, and reduced level of GSH, norepinephrine, and serotonin in the reserpine treated group. Reserpine treatment also increased brain MAO-A activity. Skimmetin/osthole treatment was found to attenuate the behavioral and biochemical alterations induced by reserpine. The results of the current investigation delineated that skimmetin/osthole may exert anti-nociceptive, anti-depressant, and improved cognition via inhibiting inflammatory and oxidative stress-mediated neurotransmitter dysregulation.

Optimization of extraction conditions of Angelica archangelica extract and activity evaluation in experimental fibromyalgia.

The plant Angelica archangelica, owing to its magnificent therapeutic effectiveness in folklore medicine system, has been regarded as an "angel plant." The current investigation was aimed to optimize extraction conditions of A. archangelica roots and to investigate in vivo role of optimized extract in fibromyalgia. Plant material (dried roots) was subjected to methanol extraction at variable temperature (40 to 60 °C) and time (12 to 36 hr) conditions as per two-factorial design strategy, and responses in terms of antioxidant activity were determined. The optimized extraction conditions were found to be temperature of 60 °C and time of 36 hr. HPLC fingerprinting indicated the presence of coumarins in extract. To induce fibromyalgia, the mice were administered reserpine at a dose of 0.5 mg/kg. Mice were orally treated with 100, 200, and 400 mg/kg extract, and magnitude of fibromyalgia was quantified. In comparison to reserpine group, the extract treatment attenuated pain as shown by significant increase in paw withdrawal threshold against mechanical stimuli (P < 0.05), improved motor ability indicated by increase in fall-off time in inclined plane test (P < 0.05), improved locomotion indicated by increased square crossings in open field test (P < 0.05), and improved cognition as shown by significant reduction in time to reach platform in Morris water maze test and passive avoidance task test (P < 0.05). Extract treatment significantly halted reserpine-induced rise in serum cytokine level (P < 0.05) and brain oxidative stress (P < 0.05). Angelica archangelica extract exerted its beneficial effects in fibromyalgia possibly through the attenuation of oxidative stress-mediated inflammatory cascade. PRACTICAL APPLICATION: Leads from natural products have become an integral part of drug designing processes and have high acceptability due to their better tolerance. The optimization of extraction conditions of plant yields better results and could reduce the processing time, thus increasing its industrial value.

Role of water in cyclooxygenase catalysis and design of anti-inflammatory agents targeting two sites of the enzyme.

While designing the anti-inflammatory agents targeting cyclooxygenase-2 (COX-2), we first identified a water loop around the heme playing critical role in the enzyme catalysis. The results of molecular dynamic studies supported by the strong hydrogen-bonding equilibria of the participating atoms, radical stabilization energies, the pKa of the H-donor/acceptor sites and the cyclooxygenase activity of pertinent muCOX-2 ravelled the working of the water-peptide channel for coordinating the flow of H·/electron between the heme and Y385. Based on the working of H·/electron transfer channel between the 12.5 Å distant radical generation and the radical disposal sites, a series of molecules was designed and synthesized. Among this category of compounds, an appreciably potent anti-inflammatory agent exhibiting IC50 0.06 µM against COX-2 and reversing the formalin induced analgesia and carageenan induced inflammation in mice by 90% was identified. Further it was revealed that, justifying its bidentate design, the compound targets water loop (heme bound site) and the arachidonic acid binding pockets of COX-2.

In Silico Studies and In Vivo MAOA Inhibitory Activity of Coumarins Isolated from Angelica archangelica Extract: An Approach toward Antidepressant Activity.

The current investigation was aimed at in vivo MAOA inhibitory activity of coumarins angelicin, bergapten, and scopoletin isolated from the roots of Angelica archangelica. The isolated compounds were screened for MAOA (pdb ID 2Z5y) binding through molecular docking studies. The molecular docking results displayed that bergapten has a maximum affinity for MAOA, followed by angelicin and scopoletin. In silico prediction of physicochemical parameters indicated that maximum blood-brain barrier (BBB) permeability was observed with angelicin (2.3), followed by bergapten (2.0) and least with scopoletin (0.644). In consonance to the results of molecular docking studies, appreciable in vivo antidepressant activity of angelicin and bergaptan was observed over the mouse model of reserpine-induced depression. The modulation of MAOA in the antidepressant effect of extract and its isolated fractions was also determined. Biochemical examination of the brain tissue indicated that bergapten has maximum MAOA inhibitory activity while scopoletin fails to inhibit brain MAOA.

Protective Effect of Esculetin, Natural Coumarin in Mice Model of Fibromyalgia: Targeting Pro-Inflammatory Cytokines and MAO-A.

Fibromyalgia is a refractory syndrome characterized by chronic wayward pain and complex co-morbid psychological trepidation. The current treatments have a limited role and proper clinical benefits are far from satisfactory. Naturally occurring coumarins such as osthole are known to have analgesic and anti-inflammatory activities. Therefore, the current investigation was designed to explore the potential of natural coumarin esculetin (2.5, 5, and 10 mg/kg) in mitigating reserpine-induced fibromyalgia in Swiss albino mice. Esculetin is a 6,7 dihydroxy-coumarin obtained from various plant sources such as Aesculus hippocastanum L, Ceratostigma willmottianum, Citrus limonia, etc. Reserpine (0.5 mg/kg/day s.c.) treatment for first 3 days, significantly altered the behavior of mice as evidenced by reduced paw withdrawal threshold in pressure application measurement (PAM) test and electronic von-Frey (eVF) test, increased immobility time in forced swim test (FST), increased latency to reach the platform in Morris water maze (MWM) test and reduced number of square crossed in the open field test (OFT). These behavioral deficits with reserpine treatment were integrated with a reduced level of serotonin (5-HT), reduced glutathione (GSH), along with an increase in monoamine oxidase-A (MAO-A) activity, pro-inflammatory cytokines (IL-1ß, TNF-α), thiobarbituric acid reactive substances (TBARS) and glutamate level. Esculetin (10 mg/kg/day i.p) treatment for 5 days, significantly abrogated reserpine induced behavioral and biochemical alterations. Whereas, no significant improvement was observed with lower doses of esculetin i.e. 2.5 and 5 mg/kg.

Ameliorative effect of imperatorin in chemically induced fibromyalgia: Role of NMDA/NFkB mediated downstream signaling.

Fibromyalgia (FM) is a chronic pain syndrome involving complex interplay of biogenic amines and NMDA receptor mediated hypersensitization of nociceptive pathways. Clinical management of FM is poorly addressed with only a few available therapeutic options. Coumarins are active phenolic molecules of natural origin found to have broad pharmacological activities. Current investigation explores the role of naturally occurring coumarin, imperatorin in mouse model of fibromyalgia. Administration of reserpine (0.5 mg/kg, s.c.) thrice at 24 h intervals induced behavioral and neurochemical alterations characteristic of fibromyalgia. Reserpine was found to induce allodynia quantified using electronic von Frey (e-VF) and pressure application measurement (PAM) test, depression as indicated by an increased duration of immobility in forced swim test (FST), decreased motor coordination and locomotor activity in inclined plane test (IPT) and open field test (OFT) respectively. Cognitive deficits were evident by an increased latency to locate hidden platform in Morris water maze (MWM) and passive avoidance test (PAT). Reserpine treatment was found to cause an increased anxiety as revealed by increased time spent in closed arm of the elevated plus maze (EPM). Furthermore, an up- regulation in NMDA and NFκB expression in the brain and spinal cord was observed in reserpine treated groups. Administration of imperatorin (10 mg/kg, i.p) for a period of 5 days ameliorated all behavioral deficits, biochemical changes and decreased expression of NMDA and NFκB in the brain and spinal cord of treated mice. These findings indicate an interplay of NMDA/NFκB modulation by imperatorin in the reserpine induced fibromyalgia in mice.

Bergapten inhibits chemically induced nociceptive behavior and inflammation in mice by decreasing the expression of spinal PARP, iNOS, COX-2 and inflammatory cytokines.

In continuation with our previous studies on osthole, bergapten, a closely related furanocoumarin was investigated for its ameliorative effect on chemically induced neurogenic and inflammatory hyperalgesia and inflammation in mice. Chemical hyperalgesia and inflammation was induced by administration of formalin (intraplantar), acetic acid (intraperitoneal) and carrageenan (intraplantar) to different groups of animals. Pain responses were quantified and median effective dose (ED50) of bergapten was calculated. Lipopolysaccharide challenge was administered to study inflammatory cytokines which were analyzed in plasma using ELISA. The expression of poly ADP-ribose polymerase (PARP), cyclooxygenase (COX-2) and inducible nitric oxide synthase (iNOS) was quantified by immnofluorescence staining. Bergapten was found to ameliorate both neurogenic and inflammatory hyperalgesia precipitated by formalin, acetic acid induced writhing and carrageenan induced paw inflammation with ED50 dose of 2.96 mg/kg. Bergapten also significantly decreased the levels of TNF-α and IL-6 and the expression of PARP, COX-2 and iNOS in the spine. It is concluded that bergapten is an interesting molecule with significant analgesic and anti-inflammatory activity emanating through the modulation of multiple pain mediating pathways.

Possible Molecular Mediators Involved and Mechanistic Insight into Fibromyalgia and Associated Co-morbidities.

Fibromyalgia is a chronic complex syndrome of non-articulate origin characterized by musculoskeletal pain, painful tender points, sleep problems and co-morbidities including depression, migraine. The etiopathogenesis of fibromyalgia is complex, variable and remains inconclusive. The etiological factors that have been defined include stress, genetic predisposition and environmental components. As per the reports of the American College of Rheumatology (ACR) the prevalence of fibromyalgia varies from 2 to 22% among the general population with poor diagnostic features primarily pain. Fibromyalgia encompasses a spectrum of co-morbid conditions with multifarious pathogenesis. The highly prevalent manifestations of fibromyalgia include heterogeneous pain and aches. Biochemical and neurobiological elements of fibromyalgia include neurotransmitters, hypothalamic pituitary adrenal axis (HPA axis), inflammatory cytokines, monoaminergic pathway, opioid peptides, sex hormones, nerve growth factor (NGF) and local free radical insult. An imbalance in the serotonergic system is the major underlying etiological factor that has been explored most widely. Owing to complex interplay of diverse pathophysiological pathways, overlapping co-morbidities such as depression have been clinically observed. Therapeutic management of fibromyalgia involves both non pharmacological and pharmacological measures. The current review presents various dysregulations and their association with symptoms of fibromyalgia along with their underlying neurobiological aspects.

Synergy of Physico-chemical and Biological Experiments for Developing a Cyclooxygenase-2 Inhibitor.

The physiological consequences of COX-2 overexpression in the development of cancer, diabetes and neurodegenerative diseases have made this enzyme a promising therapeutic target. Herein, COX-2 active site was analyzed and new molecules were designed. We identified a highly potent molecule (S)-3a with IC50 value and the selectivity for COX-2 0.6 nM and 1666, respectively. The MTD of (S)-3a was 2000 mg kg-1 and its pharmacokinetic studies in rat showed t1/2 7.5 h. This compound reversed acetic acid induced analgesia and carragennan induced inflammation by 50% and 25% in rat when used at a dose 10 mg kg-1. Mechanistically, it was found that compound (S)-3a inhibits COX-2. Overall, the combination of physico-chemical and biological experiments facilitated the development of a new lead molecule to anti-inflammatory drug.

Mercurius solubilis attenuates scopolamine-induced memory deficits and enhances the motor coordination in mice.

AIM: The present study was designed to investigate the effect of mercurius solubilis (merc sol) on scopolamine induced memory deficits and motor coordination in mice. MATERIALS AND METHODS: Three different formulations of merc sol (30X, 200M, 1M) were screened for their in vitro antioxidant potential through DPPH (2, 2-diphenyl-1-picrylhydrazyl) and nitric oxide scavenging activity using response surface methodology. Memory impairment was induced by the administration of scopolamine (1mg/kg i.p.) for 3 days to mice and assessment of memory acquisition and retention was done using Morris water maze test, passive avoidance test, elevated plus maze test, light and dark box test, motor coordination was evaluated using rotarod test and inclined plan test. The involvement of ion channels and nitric oxide pathway in the observed effect of merc sol was elucidated by administration of veratrine (0.125 µg/kg, i.p.), A23187 (20 µg/kg, i.p.), L- arginine (40 mg/kg, i.p.), aminoguanidine (50 mg/kg, i.p.) 30 min prior to merc sol. Acute toxicity studies were performed in accordance with the OECD (Organisation for Economic Co-operation and Development) guidelines. RESULTS: In vitro studies have revealed merc sol 30 X to have maximum free radical and nitric oxide scavenging activity. Administration of merc sol 30 X to mice significantly reduced scopolamine induced memory deficits and motor incoordination in all the performance tasks. The calcium ionophore, A23187 significantly altered the effect of merc sol in mice. No major signs of toxicity were observed. CONCLUSION: Merc sol has antiamnesic effect in scopolamine induced deficits and motor coordination in mice.

Curcumin alleviates ischemia reperfusion-induced acute kidney injury through NMDA receptor antagonism in rats.

OBJECTIVE: The present study investigated the role of N-methyl-d-aspartate (NMDA) receptors in curcumin-mediated renoprotection against ischemia reperfusion (I/R)-induced acute kidney injury (AKI) in rats. METHODS: Rats were subjected to bilateral renal I/R (40 min I, 24 hours R) to induce AKI. Kidney injury was assessed by measuring creatinine clearance, blood urea nitrogen, plasma uric acid, potassium level, fractional excretion of sodium, and macroproteinuria. Oxidative stress in renal tissues was assessed by measuring myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione content. Hematoxylin & eosin staining was done to assess histological changes in renal tissues. Curcumin (30 and 60 mg/kg) was administered one hour before subjecting rats to AKI. In separate groups, NMDA receptor agonists, glutamic acid (200 mg/kg), and spermidine (20 mg/kg) were administered prior to curcumin treatment in rats followed by AKI. RESULTS: I/R-induced AKI was demonstrated by significant change in plasma and urine parameters along with marked increase in oxidative stress and histological changes in renal tissues that were aggravated with pretreatment of glutamic acid and spermidine in rats. Administration of curcumin resulted in significant protection against AKI. However, glutamic acid and spermidine pretreatments prevented curcumin-mediated renoprotection. CONCLUSION: It is concluded that NMDA receptor antagonism significantly contributes towards curcumin-mediated protection against I/R-induced AKI.

Mast cell stabilizers obviate high fat diet-induced renal dysfunction in rats.

The present study investigated the infiltration of mast cells into the kidney tissue and the preventive role of mast cell stabilizers against high fat diet (HFD)-induced renal injury in rats. The animals were fed on HFD (30% fat) for 12 consecutive weeks to induce renal injury. The HFD-induced obesity was assessed by calculating obesity index, adiposity index, and estimation of total cholesterol, triglycerides, and high density lipoproteins in plasma. The renal dysfunction was evaluated by measuring creatinine clearance, blood urea nitrogen, uric acid, electrolytes and microproteinuria. The oxidative stress in renal tissues was determined by myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation and reduced glutathione level. The systolic blood pressure (SBP) was monitored using non-invasive blood pressure measuring apparatus. Histamine and hydroxyproline contents were quantified in renal tissues. Gross histopathological changes, mast cell density and collagen deposition in the renal tissue was determined by means of histopathology. The mast cell stabilizers, sodium cromoglycate and ketotifen were administered daily for 12 weeks. The HFD fed rats demonstrated significant increase in lipid profile, kidney injury with marked increase in renal oxidative stress, SBP, mast cell density, histamine content and hydroxyproline content that was attenuated by sodium cromoglycate and ketotifen treatment. Hence, the novel findings of this investigation suggest that HFD induced mast cells infiltration into kidney tissue seems to play an important role in renal pathology, and treatment with mast cell stabilizers serves as potential therapy in management of HFD induced renal dysfunction in rats.

Current status and patent prospective of animal models in diabetic research.

Diabetes mellitus is a heterogeneous complex metabolic disorder with multiple etiology which characterized by chronic hyperglycemia resulting from defects in insulin secretion, insulin action or both. The widespread occurrence of diabetes throughout the world has increased dramatically over the past few years. For better understanding, appropriate animal models that closely mimic the changes in humans needed, as vital tool for understanding the etiology and pathogenesis of the disease at the cellular/molecular level and for preclinical testing of drugs. This review aims to describe the animal models of type-1 diabetes (T1Ds) and T2Ds to mimic the causes and progression of the disease in humans. And also we highlight patent applications published in the last few years related to animal models in diabetes as an important milestone for future therapies that are aim to treating diabetes with specific symptoms and complications.

Investigation of the role of nitric oxide/soluble guanylyl cyclase pathway in ascorbic acid-mediated protection against acute kidney injury in rats.

The present study investigated the possible involvement of nitric oxide/soluble guanylyl cyclase (NO/sGC) pathway in ascorbic acid (AA)-mediated protection against acute kidney injury (AKI) in rats. The rats were subjected to bilateral renal ischemia by occluding renal pedicles for 40 min followed by reperfusion for 24 h. The AKI was assessed in terms of measuring creatinine clearance (CrCl), blood urea nitrogen (BUN), plasma uric acid, potassium level, fractional excretion of sodium (FeNa), and microproteinuria. The NO level and oxidative stress in renal tissues were assessed by measuring myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione level. AA (50 and 100 mg/kg, p.o.) was administered for 3 days before subjecting rats to AKI. In separate groups, the nitric oxide synthase inhibitor, L-NAME (20 mg/kg, i.p.) and sGC inhibitor, methylene blue (50 mg/kg, i.p.) was administered prior to AA treatment in rats. The significant decrease in CrCl and increase in BUN, plasma uric acid, potassium, FeNa, microproteinuria, and oxidative stress in renal tissues demonstrated ischemia-reperfusion-induced AKI in rats. The AA treatment ameliorated ischemia-reperfusion-induced AKI along with the increase in renal NO level. The pretreatment with L-NAME and methylene blue abolished protective effect of AA. It is concluded that AA protects against ischemia-reperfusion-induced AKI. Moreover, the NO/sGC pathway finds its definite involvement in AA-mediated reno-protective effect.

Glycine aggravates ischemia reperfusion-induced acute kidney injury through N-Methyl-D-Aspartate receptor activation in rats.

The present study was designed to investigate the role of glycine in ischemia reperfusion-induced acute kidney injury (AKI) in rats. The AKI was induced in rats by occluding renal pedicles for 40 min followed by reperfusion for 24 h. The AKI was assessed by measuring creatinine clearance, blood urea nitrogen, plasma uric acid, potassium, fractional excretion of sodium, and microproteinuria. The oxidative stress in renal tissues was assessed by quantification of myeloperoxidase activity, thiobarbituric acid-reactive substances, superoxide anion generation, and reduced glutathione level. Glycine (100, 200, and 400 mg/kg, i.p.) was administered to rats 30 min before subjecting to AKI. The glycinergic receptor blocker, strychnine (0.75 mg/kg i.p.), and glycine-binding site blocker at N-methyl-D-aspartate (NMDA) receptor, kynurenic acid (300 and 600 mg/kg i.p.), were used in the present study. The ischemia reperfusion induced AKI as witnessed by significant change in plasma, urinary, and tissue parameters employed in the present study. Glycine treatment increased ischemia reperfusion-induced AKI. The treatment with strychnine did not show any protection, whereas kynurenic acid ameliorated renal ischemia reperfusion-induced AKI. The results obtained in present study suggest that glycine increases ischemia reperfusion-induced renal damage through NMDA receptor agonism rather than strychnine-sensitive glycinergic receptors. Hence, it is concluded that glycine aggravates ischemia reperfusion-induced AKI. In addition, the activation of strychnine-insensitive glycine-binding site of NMDA receptors is responsible for its renal-damaging effect rather than strychnine-sensitive glycinergic receptors.

Comparing the metal concentration in the hair of cancer patients and healthy people living in the malwa region of punjab, India.

The cancer prevalence in the Malwa region of Punjab (1089/million/year) is much higher than the national average cancer prevalence in India (800/million/year). The participants in the present study were 50 healthy individuals and 49 cancer patients all living in the Malwa region of Punjab, with the healthy people being selected from the same household as the cancer patients. High concentrations of several potentially toxic elements were found in hair samples from people living in Punjab. Compared to standard reference ranges, the metals in excess in both the control and patient groups were aluminium (Al), barium (Ba), manganese (Mn), strontium (Sr) and uranium (U). The most significant findings were high lead (Pb), U and Ba concentrations. The maximum values for Ba, Mn, Pb and U were found in hair from breast cancer patients. The mean concentration of U in hair from the breast cancer patients was 0.63 µg U/g, which is more than double the value found in the control group and over six times higher than the reference range of 0.1 µg U/g. Water, soil, and phosphate fertilizers all seem to play a potential role, causing an increased metal burden in Punjabi people living in the Malwa region. The present study indicates that metals, and especially U, may be a factor in the development of breast cancer among Punjabi women.