Protective effect of Naringin on experimental hindlimb ischemia/reperfusion injury in rats

Protective effects of naringin on colistin-induced damage in rat testicular tissue: Modulating the levels of Nrf-2/HO-1, AKT-2/FOXO1A, Bax/Bcl2/Caspase-3, and Beclin-1/LC3A/LC3B signaling pathways

Antimicrobial agent resistance has become a growing health issue across the world. Colistin (COL) is one of the drugs used in the treatment of multidrug-resistant bacteria resulting in toxic effects. Naringin (NRG), a natural flavonoid, has come to the fore as its antioxidant, anti-inflammatory, and antiapoptotic activities. The aim of the present study was to determine whether NRG has protective effects on COL-induced toxicity in testicular tissue. Thirty-five male Spraque rats were randomly divided into five groups (n = 7 per group): Control, COL, NRG, COL + NRG 50, COL + NRG 100. COL (15 mg/kg b.w., i.p., once per/day), and NRG (50 or 100 mg/kg, oral, b.w./once per/day) were administered for 7 days. The parameters of oxidative stress, inflammation, apoptosis, and autophagic damage were evaluated by using biochemical, molecular, western blot, and histological methods in testicular issues. NRG treatment reversed the increased malondialdehyde level and reduced antioxidants (superoxide dismutase, catalase, glutathione peroxidase, and glutathione) levels due to COL administration (p < 0.001), and oxidative stress damage was mitigated. Nuclear factor erythroid 2-related factor-2 pathway, one of the antioxidant defence systems, was stimulated by NRG (p < 0.001). NRG treatment reduced the levels of markers for the pathways of apoptotic (p < 0.001) and autophagic (p < 0.001) damages induced by COL. Sperm viability and the live/dead ratio were reduced by COL but enhanced by NRG treatment. Testicular tissue integrity was damaged by COL but showed a tendency to improve by NRG. In conclusion, COL exhibited toxic effect on testicular tissue by elevating the levels of oxidative stress, apoptosis, autophagy, inflammation, and tissue damage. NRG demonstrated a protective effect by alleviating toxic damage.

Severe muscle damage after a short period of ischemia and reperfusion in an animal model

BACKGROUND

Skeletal muscle ischemia-reperfusion injuries result in a loss of contractile function, leading to limb disability or amputation. Ischemia causes hypoxia and cellular energy failure, which is aggravated by reperfusion due to the inflammatory response and oxidative stress. The consequences of the injury vary according to the duration of the period of ischemia and reperfusion. Therefore, the present work aims to evaluate ischemia-reperfusion injuries induced in the skeletal muscles of Wistar rats submitted to 3 different application periods based on morphological and biochemical parameters.

METHODS

For this, a tourniquet was applied to the root of the animals' hind limbs, occluding arterial and venous blood flow, and it was followed by reperfusion-the removal of the tourniquet. The groups were: control (without tourniquet); I30'/R60' (30 minutes of ischemia and 1 hour of reperfusion); I120'/R120' (2 hours and 2 hours); and I180'/R180' (3 hours and 3 hours).

RESULTS

All ischemia-reperfusion groups showed characteristics of muscle injury. Microscopic analyses of the extensor digitorum longus, soleus, tibialis anterior, and gastrocnemius muscles showed a significant increase in the number of injured muscle fibers in the ischemia-reperfusion groups compared to the control group. There were also significant differences between the ischemia-reperfusion groups in all muscles, showing a progressive increase in the degree of injury. The quantification of the number of injured muscle fibers between the muscles revealed that at I30'/R60', the soleus muscles had a higher number of injuries in relation to the other muscles, with statistical significance. In the I120'/R120' group, the gastrocnemius muscles presented a significantly greater number of injured fibers. There were no significant differences in the I180'/R180' group. The serum levels of creatine kinase in the I180'/R180' group were significantly higher than in the control and I30'/R60' groups.

CONCLUSIONS

Therefore, it was evident that the 3 ischemia-reperfusion models used were capable of causing cell damage, with these findings being more pronounced in the I180'/R180' group.

Therapeutic potential of naringin in improving the survival rate of skin flap: A review

Naringin is the main component of Drynaria. Modern pharmacological studies have shown that naringin has a wide range of pharmacological activities, including antioxidant, anti-inflammatory, anti-apoptotic, anti-ulcer, and anti-osteoporosis effects. Its therapeutic effects have been observed in various clinical models, such as atherosclerosis, cardiovascular diseases, diabetes, neurodegenerative diseases, and rheumatic diseases. This review investigates the pharmacological effects of naringin and the associated mechanisms in improving flap survival. This review will also provide a reference for future rational application of naringin, especially in research to improve flap survival.

Naringin Promotes Skeletal Muscle Fiber Remodeling by the AdipoR1-APPL1-AMPK Signaling Pathway

Naringin, a natural flavonoid mainly found in citrus fruit, has been reported to exert a positive effect on improving skeletal muscle health. However, the effects and potential mechanisms of naringin on skeletal muscle fiber switching is still unclear. Here, we discovered that oral administration of naringin increased the low-speed running time, four-limb hanging time, body oxygen consumption in mice, enhanced aerobic enzyme activity, MyHC I expression, and slow-twitch fiber percentage in mice skeletal muscle. By contrast, naringin decreased α-GPDH enzyme activity, MyHC IIb expression, and fast-twitch fiber percentage. Moreover, naringin increased the concentration of serum adiponectin and activated the expression of AdipoR1, APPL1, AMPK, and PGC-1α. Furthermore, by the in vitro experiment and AdipoR1 knockdown, we found that inhibition of the AdipoR1 signaling pathway significantly reduced the effect of naringin on slow-twitch fiber-/fast-twitch fiber-related gene and protein expression. In conclusion, our results indicated that naringin could induce skeletal muscle fiber transition from fast twitch to slow twitch via the AdipoR1 signaling pathway. This study may provide new strategy for improving exercise endurance and slow muscle fiber deficiency-related diseases.

Nephroprotective effect of naringin in methotrexate induced renal toxicity in male rats

The current work aims to study the nephroprotective potential of naringin (NG), a flavanone derived from citrus fruits, in methotrexate (MTX)-induced renal toxicity. Thirty male rats were divided into five groups; control group (IP saline), MTX group (IP single dose, 20 mg/kg), and three groups co-treated with MTX and naringin (IP daily dose; 20, 40, and 80 mg/kg, respectively). Kidney tissues were used to investigate renal function, oxidative stress, lipid peroxidation, and caspase-3 activity. Biochemical cytokine analysis was performed in addition to ultrastructural examinations of kidney tissue. When compared to the MTX-treated rats, MTX+NG significantly reduced the levels of urea, creatinine, MDA, NO, TNFα, IL-6, and caspase-3 activity. A significant increase in the levels of the antioxidant enzymes and GSH were also noted. Additionally, naringin ameliorated the apparent ultrastructural changes observed in the glomeruli and renal tubules of MTX-intoxicated rats. Noticeable structural improvements of glomerular lesions, proximal, and distal convoluted tubular epithelium were observed in MTX+NG treated animals, including podocytes with regular foot processes, perfectly organized filtration barrier, no signs of GBM thickening, organized brush border, and normal architecture of microvilli. Naringin (80 mg/kg) had the maximum amelioration effect. To the best of our knowledge, this is the first study to investigate the ultrastructural manifestations of naringin and/or MTX on the kidney of rats. Taken all, naringin has a potent therapeutic effect and can be used in adjuvant therapy to prevent MTX-induced nephrotoxicity. Nevertheless, the molecular mechanism underlying the nephroprotective capacity of naringin needs further investigation.

Effects of Trans-Cinnamaldehyde on Reperfused Ischemic Skeletal Muscle and the Relationship to Laminin

PURPOSE

Ischemia-reperfusion (I-R) injury is a serious problem caused by vascular trauma, tourniquet use and/or compartment syndrome. Studies have reported that skeletal muscle function is impaired due to the lower extremity I-R injury. There are insufficient studies on the treatment methods used for the recovery of dysfunction. This study is designed to investigate the effects of trans-cinnamaldehyde (TCA), a volatile oil of cinnamon structure, on the contractile dysfunction due to I-R injury of rat extensor-digitorum-longus (EDL) muscle.

MATERIALS AND METHODS

Sprague-Dawley rats were randomly divided into three groups. Except for the animals in the control group, all animals received saline (3-ml/kg) or TCA solution (30-mg/kg) which was administered orally three times with an 8-h interval before ischemia. After 24-hours, experimental groups were subjected to 3-h of lower extremity ischemia followed by 5-h reperfusion period. Then, the compound muscle action potential (CMAP) and mechanical activity of muscle were recorded using the standard electro-biophysical techniques.

RESULTS

There was a decrease in the maximum contractile force in I-R group compared to the control group (p < 0.05). Oxidative damage indicator (MDA) and antioxidant indicator (CAT) increased in the EDL muscle and serum samples in the I-R group (p < 0.05). Laminin expression showed a reduction in the I-R group (p < 0.05). It was seen that TCA achieve again the maximum contraction force in the EDL muscle (p < 0.05) and maintain the expression of laminin (p > 0.05).

CONCLUSION

We concluded that TCA has a potential protective effect with antioxidant effects against I-R injury and may maintain laminin levels.

Naringin Targets NFKB1 to Alleviate Oxygen-Glucose Deprivation/Reoxygenation-Induced Injury in PC12 Cells Via Modulating HIF-1α/AKT/mTOR-Signaling Pathway

This study was designed to investigate the effect of naringin in oxygen-glucose deprivation/reoxygenation (OGD/R) model and its mechanism. The target gene of naringin and the enriched pathways of the gene were searched and identified using bioinformatics analysis. Then OGD/R model was built using PC12 cells, after which the cells were treated with different concentrations of naringin. Subsequently, cell proliferation and apoptosis were evaluated by cell counting kit-8 (CCK-8) and flow cytometry assays, respectively. Meanwhile, the expression of NFKB1 in PC12 cells underwent OGD/R-induced injury was detected by qRT-PCR, while apoptosis-related and pathway-related proteins were checked by Western blot. DCF-DA kit was utilized to measure the level of ROS. Our results revealed that NFKB1, which was upregulated in MACO rats and OGD/R-treated PC12 cells, was a target gene of naringin. Naringin could alleviate OGD/R-induced injury via promoting the proliferation, and repressing the apoptosis of PC12 cells through regulating the expression of NFKB1 and apoptosis-associated proteins and ROS level. Besides, the depletion of NFKB1 was positive to cell proliferation but negative to cell apoptosis. Moreover, the depletion of NFKB1 enhanced the influences of naringin on cell proliferation and apoptosis as well as the expression of apoptosis-related proteins and ROS level. Western blotting indicated that both naringin treatment and depletion of NFKB1 could increase the expression of HIF-1α, p-AKT, and p-mTOR compared with OGD/R group. What's more, treatment by naringin and si-NFKB1 together could significantly increase these effects. Nevertheless, the expression of AKT and mTOR among each group was almost not changed. In conclusion, naringin could prevent the OGD/R-induced injury in PC12 cells in vitro by targeting NFKB1 and regulating HIF-1α/AKT/mTOR-signaling pathway, which might provide novel ideas for the therapy of cerebral ischemia-reperfusion (I/R) injury.

Riluzole protects against skeletal muscle ischaemia-reperfusion injury in a porcine model

INTRODUCTION

Skeletal muscle ischaemia-reperfusion injury (IRI) can be a life threatening condition. It is relevant to various aspects of the management of trauma and surgical patients. Currently there lacks a pharmacological agent that can be used to dampen the effects of IRI. Riluzole has been shown to reduce the effects of IRI on various organ systems, but there have yet to be any studies on the effects in IRI of skeletal muscle. Our aim was to investigate the effects of Riluzole on IRI in the skeletal muscle of pigs.

METHODS

Twenty-two pigs were randomly divided into groups. Riluzole was administered before ligation of the femoral artery to produce ischaemia in the tibialis anterior muscle in the experimental group but not the control group. The microscopic appearance of muscles were recorded, a TUNEL assay was used to identify DNA damage and glutathione levels were measured.

RESULTS

In the Riluzole group, muscle fibres appeared less wavy and less oedematous compared to the control group. The Riluzole group also had less evidence of DNA fragmentation on the TUNEL assay. The glutathione levels in the Riluzole group were also significantly greater than the control group.

DISCUSSION

Our findings suggest that Riluzole can potentially reduce the effects of IRI on skeletal muscle. This is potentially due to the ability of Riluzole to block sodium channels, decreasing action potentials and therefore glutamate release. It also acts to decrease intracellular calcium levels, which prevents apoptosis. Riluzole is a promising drug for the prevention of IRI in skeletal muscle, but further research is required.

Protective effects of epigallocatechin gallate against ischemia reperfusion injury in rat skeletal muscle via activating Nrf2/HO-1 signaling pathway

AIMS

Previous studies have demonstrated that epigallocatechin gallate (EGCG) had certain protective effects on myocardial and renal ischemia reperfusion (I/R) injury. We aimed to research the special effects and underling mechanisms of EGCG on skeletal muscle I/R injury.

MAIN METHOD

We established an experimental rat model of I/R skeletal muscle injury and treated with different doses of EGCG. Hematoxylin eosin staining, TUNEL assay, ELISA, qRT-PCR and Western blotting were used to evaluate the effects of EGCG.

KEY FINDINDS

EGCG significantly improved skeletal muscle function of I/R injury rats. Moreover, EGCG had positive effects on decreasing apoptosis of skeletal muscle tissues, alleviating oxidative stress damage and suppressing the production of inflammatory cytokines. Further, EGCG had positive effects on activating Nrf2/HO-1 signaling pathway.

SIGNIFICANCE

EGCG might be a powerful candidate compound for alleviating I/R injury in rat skeletal muscle.

[Prehospital application of tourniquets for life-threatening extremity hemorrhage : Systematic review of literature]

INTRODUCTION

The effectiveness of a tourniquet in the case of life-threatening hemorrhages of the extremities is well recognized and led to the recommendations on "Tourniquet" of the German Society of Anaesthesiology and Intensive Care (DGAI) in 2016. The aim of this systematic review was to re-evaluate the current medical literature in relation to the published DGAI recommendations.

MATERIAL AND METHODS

Based on the analysis of all studies published from January 2015 until January 2018 in the PubMed databases, the publicized recommendations for action on "Tourniquet" of the DGAI were critically re-evaluated. For this purpose, 17 questions on 6 subjects were formulated in advance. The systematic review followed the PRISMA recommendations and is registered in PROSPERO (International prospective register of systematic reviews, Reg.-ID: CRD42018091528).

RESULTS

Of the 284 studies identified with the keywords tourniquet and trauma in the period from January 2015 to January 2018 in PubMed, 50 original papers discussing the prehospital application of tourniquet for life-threatening hemorrhage of the extremities were included. The overall level of evidence is low. No article addressed any of the formulated questions with a prospective randomized interventional study. Scientific deductions could be found only in an indirect way in a descriptive manner.

CONCLUSION

The 50 original articles included in this qualitative, systematic review revealed that the recommendations "Tourniquet" of the DGAI published in 2016 are mostly still up to date despite an inhomogeneous study situation. A deviation occurred in the conversion of a tourniquet but due to the short prehospital treatment time in the civilian setting this is of little importance; however, in the future a strict distinction should be made between tourniquets which were placed for tactical reasons and those placed as a medical necessity.

Activation of cannabinoid type 2 receptor protects skeletal muscle from ischemia-reperfusion injury partly via Nrf2 signaling

AIMS

Cannabinoid type 2 (CB₂) receptor activation has been shown to attenuate IRI in various organs. NF-E2-related factor (Nrf2) is an anti-oxidative factor that plays multiple roles in regulating cellular redox homeostasis and modulating cell proliferation and differentiation. The protective effects of CB₂ receptor activation on skeletal muscle IRI and the underlying mechanism that involves Nrf2 signaling remain unknown.

MAIN METHODS

We evaluated the in vivo effect of CB₂ receptor activation by the CB₂ receptor agonist AM1241 on IR-induced skeletal muscle damage and early myogenesis. We also assessed the effects of CB₂ receptor activation on C2C12 myoblasts differentiation and H₂O₂-induced C2C12 myoblasts damage in vitro, with a focus on the mechanism of Nrf2 signaling.

KEY FINDINGS

Our results showed that CB₂ receptor activation reduced IR-induced histopathological lesions, edema, and oxidative stress 1 day post-injury and accelerated early myogenesis 4 days post-injury in mice. Nrf2 knockout mice that were treated with AM1241 exhibited deteriorative skeletal muscle oxidative damage and myogenesis. In vitro, pretreatment with AM1241 significantly increased the expression of Nrf2 and its nuclear translocation, attenuated the decrease in H₂O₂-induced C2C12 cell viability, and decreased reactive oxygen species generation and apoptosis. CB₂ receptor activation also significantly enhanced C2C12 myoblasts differentiation, which was impaired by silencing Nrf2.

SIGNIFICANCE

Overall, CB₂ receptor activation protected skeletal muscle against IRI by ameliorating oxidative damage and promoting early skeletal muscle myogenesis, which was partly via Nrf2 signaling.

Coenzyme Q10 attenuates lung and liver fibrosis via modulation of autophagy in methotrexate treated rat

The present study was conducted to investigate the potential protective effects of coenzyme Q 10 (CoQ10) administration on methotrexate induced lung and liver fibrosis in rat model, and to explore our hypothesis regarding its possible mechanism of action through reactivation of autophagy pathway. Methotrexate induced fibrosis was achieved by intraperitoneal injections twice a week for 4 weeks. A combined treatment of CoQ10 and methotrexate were used. Blood samples for biochemical analysis, lung and livers tissue for biochemical and histopathological analysis, were investigated. Concomitant treatment of CoQ10 & methotrexate caused improvement in histological picture of the lung and liver tissues, liver function and oxidative stress biomarkers, modulation of autophagy genes [mammalian target of rapamycin (m-TOR), Microtubule-associated proteins 1 A/1B light chain 3 (MAP1LC3B), and Sequestosome 1 ubiquitin-binding protein p62 (p62/SQSTM1)] with simultaneous reduction in High Mobility Group Protein B1 (HMGB1). Based on our results we postulated that CoQ10 up regulates autophagy pathway that could explain its protective properties against lung and liver fibrosis caused by methotrexate treatment in current study rat model.

Investigation of the effects of naringin on intestinal ischemia reperfusion model at the ultrastructural and biochemical level

We aimed to evaluate the ultrastructural effect of reversing cellular damage, occurring in rats due to ischemia-reperfusion (I/R) in the intestine, with naringin implementation through biochemical parameters. Rats were divided the sham/control, I/R and the naringin groups (n = 7). For I/R group, 120 min of ischemia and 120 min of reperfusion was applied to the superior mesenteric artery. In the naringin group, after 120 min, 50 mg/kg naringin was implemented, and then 120 min of reperfusion was applied. Morphological evaluation was performed via Chiu score and electron microscopy. The antioxidant parameters were examined. Chiu score in I/R (p < 0.01) and naringin (p < 0.05) groups were higher than the sham/control group. In ultrastructural level some irregularity were observed in I/R group. Although it decreased in the naringin group, the damage was observed to continue. Malondialdehyde (MDA) amount and Superoxide dismutase activity (SOD) in I/R group were higher in comparison to the sham/control group (p < 0.01), while glutathione peroxidase activity (Gpx) was found to be lower (p < 0.01). SOD (p < 0.05) and MDA (p < 0.01) were decreased by naringin group. Gpx was decreased in I/R group compared to sham/control group (p < 0.01) and elevated due to naringin administration (p < 0.05). Catalase activity was observed to decrease in the naringin group compared to control and I/R groups (p < 0.01). It was determined that naringin provided limited healing at the ultrastructural level but also effected recovery within antioxidant parameters.

The Protective Effects of p-Coumaric Acid on Acute Liver and Kidney Damages Induced by Cisplatin

In this study, we aimed to investigate the effects of p-Coumaric acid (PCA) on cisplatin (CIS)-induced hepatotoxicity and nephrotoxicity in Wistar adult rats for 24 h compared to untreated control groups. In this experiment, 40 Wistar adult rats were utilized and divided randomly into five groups. After 24 h of CIS administration, liver and kidneys were harvested and assessed by H&amp;E staining. Also, markers for oxidative stress and antioxidants were analyzed in theses tissues. Compared to the control group, accumulation of malondialdehyde was increased in groups treated CIS, whereas superoxide dismutase activities and glutathione levels were distinctly diminished in this group. The study's histopathological findings such as hydropic degeneration, vascular congestion, sinusoidal dilatation in hepatocytes and tubular necrosis in kidneys were in accordance with the results of markers for oxidative stress. PCA may prevent hepatotoxicity and nephrotoxicity by increased antioxidant enzymes and reduced oxidant parameters.