Effects of Folinic Acid Administration on Lower Limb Ischemia/Reperfusion Injury in Rats

The Effect of "Proanthocyanidin" on Ischemia-Reperfusion Injury in Skeletal Muscles of Rats

Background and Objectives: Lower limb skeletal muscle ischemia-reperfusion (IR) injury is associated with increased morbidity and mortality, and it is common in several clinical situations such as aortic aneurysms repairment, peripheral arterial surgery, vascular injury repairment, and shock. Although it is generally accepted that oxidative stress mediators have a significant role in IR injury, its precise mechanism is still unknown. Anecdotally, it is sustained not only by structural and functional changes in the organ it affects but also by damage to distant organs. The purpose of this report is to illustrate the effect of proanthocyanidin on IR injury. Materials and Methods: In our study, 18 male Wistar albino rats were used. The subjects were divided into three groups containing six mice each (control, C; ischemia-reperfusion, IR; ischemia-reperfusion and proanthocyanidin; IR-PRO). Intraperitoneal proanthocyanidin was given to the IR and proanthocyanidin groups 30 min before laparotomy, and 1 h ischemia led to these two groups. After one hour, reperfusion started. Muscle atrophy-hypertrophy, muscle degeneration-congestion, fragmentation-hyalinization, muscle oval-central nucleus ratio, leukocyte cell infiltration, catalase enzyme activity, and TBARS were all examined in lower-limb muscle samples after one hour of reperfusion. Results: When skeletal muscle samples were evaluated histopathologically, it was discovered that muscle atrophy-hypertrophy, muscle degeneration-congestion, fragmentation-hyalinization, and leukocyte cell infiltration with oval-central nucleus standardization were significantly higher in the IR group than in the C and IR-P groups. Oval-central nucleus standardization was significantly higher in the IR and IR-PRO groups than in the control group. TBARS levels were significantly higher in the IR group than in the control and IR-PRO groups, while catalase enzyme activity was found to be significantly lower in the IR group than in the control and IR-PRO groups. Conclusions: As a consequence of our research, we discovered that proanthocyanidins administered before IR have a protective impact on skeletal muscle in rats. Further research in this area is required.

Effect of miR-206 on lower limb ischemia-reperfusion injury in rat and its mechanism

Lower limb ischemia-reperfusion is a common pathological process during clinical surgery. Because lower limb ischemia-reperfusion usually aggravates ischemia-induced skeletal muscle tissue injury after lower limb ischemia-reperfusion, it also causes remote organ heart, intestine, liver, lung and other injuries, and there is no effective clinical treatment for lower limb ischemia-reperfusion injury, so it is urgent to study its injury mechanism. In this study, the rat model of lower limb ischemia-reperfusion was established by clamping the femoral artery with microarterial clips, and the wall destruction such as intimal injury, cell edema, collagen degeneration, neutrophil infiltration, and elastic fiberboard injury of the femoral artery wall was detected. The expression of inflammatory factors was detected by immunohistochemistry. miR-206 preconditioning was used to observe the expression of inflammatory factors, redox status and apoptosis in the vascular wall of rats after acute limb ischemia-reperfusion. Our findings suggest that vascular endothelial cell edema increases, wall thickening, neutrophil infiltration, and elastic fiber layer damage during IRI. Inflammatory factor expression was increased in femoral artery tissue, and miR-206 expression levels were significantly down-regulated. Further studies have found that miR-206 attenuates lower limb IRI by regulating the effects of phase inflammatory factors. In this study, we investigated the effect of miR-206 on inflammatory factors and its possible role in the development of lower limb IRI, providing new research ideas for the regulatory mechanism of lower limb IRI, and providing a certain theoretical basis for the treatment of lower limb ischemia-reperfusion injury after surgery or endovascular intervention.

Syringic acid suppresses ferroptosis of skeletal muscle cells to alleviate lower limb ischemia/reperfusion injury in mice via the HMGB1 pathway

Ischemia/reperfusion (I/R) of skeletal muscle in the lower limbs is an important factor affecting the outcome of lower limbs ischemia patients, with no effective preventive or therapeutic approaches available. The study was to investigate the effect of syringic acid (SA) on I/R skeletal muscle in the lower limbs injury. Mice femoral artery I/R models and C2C12 cell hypoxia/reoxygenation (H/R) models was establish, tissue damage, inflammatory status, and high mobility group box 1 (HMGB1) pathway were evaluated using histological analysis, enzyme-linked immunosorbent assay, and western blotting. Further, the study detected the effect of SA on cell apoptosis, lipid peroxidation, Fe2+ level, and ferroptosis-related proteins expression. Finally, the effect of HMGB1 expression on SA in H/R stimulation was studied. SA alleviated pathological damage and reduced levels of IL-1β, IL-6, and TNF-α in muscle tissues from femoral artery I/R mouse models. SA upregulated Bcl-2 and SOD as well as downregulated Bax, MDA, TBARS content, and Fe2+ level in H/R-induced cells. SA inhibited HMGB1 expression and promoted Nrf2, HO-1, GPX4, and SLC7A11 expressions in the injured tissues and cells. Such effects of SA on H/R-induced cells were rescued by HMGB1 overexpression. SA suppressed ferroptosis of skeletal muscle cells to alleviate lower limb I/R injury in mice by blocking the HMGB1 pathway, providing new insights for the treatment of lower limb ischemia-reperfusion injury.

Prophylactic Treatment of Intestinal Ischemia-Reperfusion Injury Reduces Mucosal Damage and Improves Intestinal Absorption

Purpose

Intestinal ischemia-reperfusion injury (i-IRI) involves a blood flow interruption in an intestinal segment followed by blood flow restoration. When blood flow is restored, oxidative and inflammatory molecules are distributed throughout the bloodstream, triggering both local and systemic damage. Our goal was to evaluate the potential of three antioxidant and/or anti-inflammatory compounds (curcumin, dexmedetomidine and α-tocopherol) to prevent or reverse local and systemic damage induced by i-IRI.

Methods

i-IRI was induced by placing a microvascular clip in the superior mesenteric artery of female WAG/RijHsd rats; the clip was removed after 1h and reperfusion was allowed for 4h. Curcumin (200 mg/kg, orally), α-tocopherol (20 mg/kg, i.p.), and dexmedetomidine (5 or 20 µg/kg, s.c.; DEX5 and DEX20, respectively) were administered. Blood and terminal ileum specimens were collected for biochemical and histological determination. Furthermore, D-xylose absorption test was performed to evaluate intestinal absorption; after completing the 1-hour ischemia and 4-hour reperfusion period, 1 mL of aqueous D-xylose solution (0.615 mg/mL) was administered orally, and one hour later, plasma D-xylose levels were quantified.

Results

The histological injury degree (HID) measured by the Chiu scale was significantly reduced when the treatments were applied (non-treated rats, 2.6 ± 0.75; curcumin, 1.54 ± 0.8; DEX5, 1.47 ± 0.7; DEX20 1.14 ± 0.5; and α-tocopherol, 1.01 ± 0.6); intestinal absorptive capacity also improved in all cases healthy rats (2.06 ± 0.07 µg/mL; non-treated, 1.18 ± 0.07 µg/mL; curcumin 1.76 ± 0.3 µg/mL; DEX5, 2.29 ± 0.2 µg/mL; DEX20, 2.25 ± 0.26 µg/mL; and α-tocopherol 1.66 ± 0.21 µg/mL). However, it failed to reduce liver enzyme levels. Finally, only dexmedetomidine significantly reduced urea and creatinine levels compared to non-treated animals.

Conclusion

All drugs were effective in reducing HID, although α-tocopherol was effective to a greater extent. Only dexmedetomidine reverted intestinal absorption to normal values of healthy animals.

The Prevention of Ischemia-Reperfusion Injury in Elderly Rats after Lower Limb Tourniquet Use

Background: Lower limb ischemia-reperfusion injury (IRI-LL) is a common major complication of orthopedic surgery, especially in elderly patients. It has previously been demonstrated that folinic acid (FA) reduced IRI-LL damage in 3−4-month-old rats. This current work analyses the effect of FA in the prevention of IRI-LL in elderly animals. Methods: Forty-two 18-month-old male WAG/RijHsd rats were subjected to 3 h of ischemia. Eighteen animals received FA (2.5 mg/kg, ip) 20 min before the end of the ischemia period, while the other half received the same volume of saline solution. The animals were sacrificed after 3 h, 24 h, and 14 days of reperfusion for biochemical (tissue damage markers and electrolytes), histopathological studies of the gastrocnemius muscle and the daily assessment of the limb function by the Rota Rod test, respectively. Results: The administration of FA prior to the end of the ischemia period reduced the increase in LDH and CK observed in non-treated animals by 30−40% (p < 0.0001). When the histological sections were analyzed, FA was found to have reduced the number of damaged muscle fibers per field by 20% (60 ± 17.1 vs. 80.7 ± 16.4, p < 0.0001). The functional test revealed that FA also led to an improvement in the muscle function, assessed by the length of time that the animals kept running on the rod, compared to untreated animals. Conclusions: The administration of FA, prior to the end of the ischemic period, decreases the damage induced by IRI-LL, also achieving a faster recovery of mobility.

Clinical Efficacy Analysis of Fast Rehabilitation Nursing on Pain Mitigation after Lumbar Discectomy and Bone Graft Fusion and Internal Fixation

Objective

To investigate clinical efficacy analysis of fast rehabilitation nursing on pain mitigation after lumbar discectomy and bone graft fusion and internal fixation.

Methods

A total of 60 patients with lumbar disc herniation who underwent lumbar discectomy and bone graft fusion and internal fixation in our hospital from January 2021 to December 2021 were randomized either into routine group (n = 30) or rehabilitation group (n = 30) via the random number table method. The patients in the routine group were intervened with the routine postoperative nursing mode, and the patients in the rehabilitation group were intervened with the fast rehabilitation nursing mode on the basis of the nursing of the patients in the routine group. The rehabilitation effect, self-rating anxiety scale (SAS) and self-rating depression scale (SDS) scores, postoperative pain improvement, and nursing satisfaction were compared between the two groups.

Results

The postoperative rehabilitation effect of the rehabilitation group was significantly better than that of the routine group (P < 0.05). The fast rehabilitation nursing resulted in a notably lower postoperative SAS and SDS scores versus the routine nursing (P < 0.001). The postoperative pain was significantly mitigated in the rehabilitation group when compared with the routine group (P < 0.001). The fast rehabilitation nursing implemented in the rehabilitation group led to a remarkably higher nursing satisfaction of the patients (P < 0.001).

Conclusion

The fast rehabilitation nursing mode intervention for lumbar disc herniation patients undergoing lumbar discectomy and bone graft fusion and internal fixation is a promising approach to improve the postoperative rehabilitation, mitigate postoperative pain, and relieve anxiety, depression, and other negative emotions, with higher clinical nursing satisfaction.