Mesenchymal stem cells derived-exosomes enhanced amniotic membrane extract promotes corneal keratocyte proliferation.

Amniotic membrane extract (AME) and Wharton's jelly mesenchymal stem cells derived-exosomes (WJ-MSC-Exos) are promising therapeutic solutions explored for their potential in tissue engineering and regenerative medicine, particularly in skin and corneal wound healing applications. AME is an extract form of human amniotic membrane and known to contain a plethora of cytokines and growth factors, making it a highly attractive option for topical applications. Similarly, WJ-MSC-Exos have garnered significant interest for their wound healing properties. Although WJ-MSC-Exos and AME have been used separately for wound healing research, their combined synergistic effects have not been studied extensively. In this study, we evaluated the effects of both AME and WJ-MSC-Exos, individually and together, on the proliferation of corneal keratocytes as well as their ability to promote in vitro cell migration, wound healing, and their impact on cellular morphology. Our findings indicated that the presence of both exosomes (3 × 105 Exo/mL) and AME (50 µg/mL) synergistically enhance the proliferation of corneal keratocytes. Combined use of these solutions (3 × 105 Exo/mL + 50 µg/mL) increased cell proliferation compared to only 50 µg/mL AME treatment on day 3 (**** p < 0.0001). This mixture treatment (3 × 105 Exo/mL + 50 µg/mL) increased wound closure rate compared to isolated WJ-MSC-Exo treatment (3 × 105 Exo/mL) (*p < 0.05). Overall, corneal keratocytes treated with AME and WJ-MSC-Exo (3 × 105 Exo/mL + 50 µg/mL) mixture resulted in enhanced proliferation and wound healing tendency. Utilization of combined use of AME and WJ-MSC-Exo can pave the way for a promising foundation for corneal repair research.

Clinical Applications of Combined Immunotherapy Approaches in Gastrointestinal Cancer: A Case-Based Review.

Malignant neoplasms arising from the gastrointestinal (GI) tract are among the most common types of cancer with high mortality rates. Despite advances in treatment in a small subgroup harboring targetable mutations, the outcome remains poor, accounting for one in three cancer-related deaths observed globally. As a promising therapeutic option in various tumor types, immunotherapy with immune checkpoint inhibitors has also been evaluated in GI cancer, albeit with limited efficacy except for a small subgroup expressing microsatellite instability. In the quest for more effective treatment options, energetic efforts have been placed to evaluate the role of several immunotherapy approaches comprising of cancer vaccines, adoptive cell therapies and immune checkpoint inhibitors. In this review, we report our experience with a personalized dendritic cell cancer vaccine and cytokine-induced killer cell therapy in three patients with GI cancers and summarize current clinical data on combined immunotherapy strategies.

Effectiveness of Mesenchymal Stem Cell Therapy for COVID-19 Patients in the Intensive Care Unit: A Case-Control Study

Objective: Many methods are used in the treatment of coronavirus disease 2019 (COVID-19), which causes acute respiratory distress syndrome (ARDS), and there are conflicting reports in the literature regarding the results of mesenchymal stem cell (MSC) therapy, which is one of those methods. The aim of our study is to evaluate the effect of MSC treatment applied together with standard treatments on survival. Materials and Methods: This retrospective case-control study evaluates the survival effect of MSC treatment administered to patients treated in intensive care after the development of ARDS due to COVID-19 between March 2020 and March 2021. The age, gender, comorbid disease status, APACHE II score, and overall and comorbidity-based survival rates were compared between patients who received standard medical treatment (SMT) and patients who received MSC treatment together with SMT. Results: There were 62 patients in the group receiving only SMT and 81 patients in the group receiving SMT and MSC. No difference was observed between the groups in terms of age, gender, presence of comorbid diseases, or APACHE II scores. There were also no differences according to Kaplan-Maier analysis for the survival statuses of the groups. There was no serious adverse effect due to MSC treatment among these patients. Conclusion: Our study presents the largest case series in the literature, and it was observed that MSC treatment may not significantly affect overall survival or comorbid disease-based survival, in contrast to many other studies in the literature.

Mesenchymal stem cells have ameliorative effect on the colitis model via Nrf2/HO-1 pathway.

PURPOSE: To evaluate the ameliorative effect of mesenchymal stem cells (MSCs) on acetic acid colitis model via Nrf2/HO-1 pathway in rats. METHODS: In this study, 30 rats were divided into three groups. Acute colitis was induced by rectal administration of 4% solution of acetic acid. MSCs were injected intraperitoneally in the treatment group. RESULTS: Increased levels of tumor necrosis factor-α (TNF-α), pentraxin-3, and malondialdehyde (MDA) in colitis group were revealed biochemically. Increased level of TNF-α and decreased levels of Nrf2 and interleukin-10 (IL-10) were observed in rectum tissues. Increased fibrous tissue proliferation, vascularization and inflammatory cell infiltration were described in the colitis group. Significant improvement was observed in MSCs treated group histopathologically. Increased immunopositivity of TNF-α, vascular endothelial growth factor (VEGF) and CD68 markers was observed in the colitis group cells, and decreased level of this positivity was observed in MSCs treated group. CONCLUSIONS: Biochemical, histopathological and immunohistochemical results strongly support the ameliorative effect of MSCs against acetic induced colitis model via Nrf2/HO-1 pathway in rats.

Mesenchymal stem cells have ameliorative effect on the colitis model via Nrf2/HO-1 pathway

Purpose: To evaluate the ameliorative effect of mesenchymal stem cells (MSCs) on acetic acid colitis model via Nrf2/HO-1 pathway in rats. Methods: In this study, 30 rats were divided into three groups. Acute colitis was induced by rectal administration of 4% solution of acetic acid. MSCs were injected intraperitoneally in the treatment group. Results: Increased levels of tumor necrosis factor-α (TNF-α), pentraxin-3, and malondialdehyde (MDA) in colitis group were revealed biochemically. Increased level of TNF-α and decreased levels of Nrf2 and interleukin-10 (IL-10) were observed in rectum tissues. Increased fibrous tissue proliferation, vascularization and inflammatory cell infiltration were described in the colitis group. Significant improvement was observed in MSCs treated group histopathologically. Increased immunopositivity of TNF-α, vascular endothelial growth factor (VEGF) and CD68 markers was observed in the colitis group cells, and decreased level of this positivity was observed in MSCs treated group. Conclusions: Biochemical, histopathological and immunohistochemical results strongly support the ameliorative effect of MSCs against acetic induced colitis model via Nrf2/HO-1 pathway in rats.

The effects of IGF-1 and erythropoietin on apoptosis and telomerase activity in necrotizing enterocolitis model.

BACKGROUND: Apoptosis that occurs after hypoxia/reoxygenation (H/R) has an important role in the pathogenesis of necrotizing enterocolitis (NEC). Telomerase activity, showing the regeneration capacity, may also be important in the recovery process. Therefore, we aimed to investigate the effects of insulin-like growth factor-1 (IGF-1) and erythropoietin (EPO) on apoptosis and telomerase activity in an H/R model. METHODS: Young mice were divided into four groups each containing ten Balb/c mice. Group 1 (H/R) were exposed to H/R; group 2 and group 3 were pretreated with IGF-1 and EPO, respectively, for 7 days before H/R. Group 4 served as control. Intestinal injury was evaluated by histological scoring and assessment of apoptosis was performed by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) test. Proapoptotic and antiapoptotic gene expressions and telomerase activity were analyzed by real-time PCR. RESULTS: IGF-1- and EPO-treated animals had decreased histological damage and apoptosis, confirmed by TUNEL test and caspase activity. Telomerase activity was increased in these animals in addition to increased expression of antiapoptotic genes. However, proapoptotic gene expressions were not statistically different. CONCLUSIONS: The protective effects of IGF-1 and EPO in H/R damage may be through increased expression of antiapoptotic genes and increased telomerase activity, especially for IGF-1. IMPACT: This is a comprehensive study measuring various variables, namely IGF-1, EPO, apoptosis, apoptotic and antiapoptotic genes, and telomerase activity in the NEC model. The intestinal protective effects of IGF-1 and EPO in H/R damage may occur through increased expression of antiapoptotic genes and increased telomerase activity. To the best of our knowledge, telomerase activity has not been investigated in the NEC model before. Regarding our results, novel strategies may be implemented for the early definitive diagnosis, robust preventive measures, and effective treatment modalities for NEC.

Multi-parametric evaluation of autologous cultivated Limbal epithelial cell transplantation outcomes of Limbal stem cell deficiency due to chemical burn.

BACKGROUND: The sparsity of established tools for the grading of limbal stem cell deficiency hinder objective assessments of the clinical outcome of cultivated limbal epithelial cell transplantation. To advance towards the development of standards for the comparison of the outcomes of these bio-surgical protocols we have now applied a battery of recognized objective and patient-declared subjective outcome criteria to the autologous modality of cultivated limbal epithelial cell transplantation. METHODS: The prospective study involved ten patients (M/F = 9/1; mean age = 42.1 years) displaying overt unilateral limbal stem cell deficiency complying with the inclusion criteria described in Methods. Limbal biopsies were obtained from the contralateral eye and their outgrowths after 2-week cultures were transplanted on the affected eye after pannus resection. Outcomes were followed up for 12 months. The objective tests were scores for best-corrected visual acuity (BCVA); using the LogMAR scale, a multiparametric ocular surface score (OSS), and the Schirmer's test. Subjective scores were based on patient answers to a) perception of visual improvement/pain; b) the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ 25); and c) the 12-item Ocular Surface Disease Index Questionnaire (OSDI). All procedures were performed under good manufacture practices using solely xeno-free reagents. In all cases, a single biopsy was divided into two pieces and they were expanded in order to prevent outgrowth failure. In 5 patients, both biopsies generated healthy culture sheet. In those cases the lesser outgrowth were used for immune-histological characterization. RESULTS: The experimental parallel outgrowth samples showed a similar percent of p63α+ cells. PreOp and 12-month PostOp BCVAs and OSSs were, respectively, 1.15 ± 0.70; 0.21 ± 0.13 and 7.40 ± 2.01; 2,30 ± 1.30, (p < 0.05). Patient's responses to all three question sets except ocular pain were consistent with significant improvement (p < 0.05). CONCLUSION: Objective clinical metrics demonstrate that in patients with limbal stem cell deficiency, cultivated limbal epithelial cell transplantation improves vision and ocular surface health and subjective visual perceptions.

Limbal Stem Cell Deficiency and Treatment with Stem Cell Transplantation.

The cornea is the outermost tissue of the eye and it must be transparent for the maintenance of good visual function. The superficial epithelium of the cornea, which is renewed continuously by corneal stem cells, plays a critical role in the permanence of this transparency. These stem cells are localized at the cornea-conjunctival transition zone, referred to as the limbus. When this zone is affected/destroyed, limbal stem cell deficiency ensues. Loss of limbal stem cell function allows colonization of the corneal surface by conjunctival epithelium. Over 6 million people worldwide are affected by corneal blindness, and limbal stem cell deficiency is one of the main causes. Fortunately, it is becoming possible to recover vision by autologous transplantation of limbal cells obtained from the contralateral eye in unilateral cases. Due to the potential risks to the donor eye, only a small amount of tissue can be obtained, in which only 1-2% of the limbal epithelial cells are actually limbal stem cells. Vigorous attempts are being made to expand limbal stem cells in culture to preserve or even enrich the stem cell population. Ex vivo expanded limbal stem cell treatment in limbal stem cell deficiency was first reported in 1997. In the 20 years since, various protocols have been developed for the cultivation of limbal epithelial cells. It is still not clear which method promotes effective stem cell viability and this remains a subject of ongoing research. The most preferred technique for limbal cell culture is the explant culture model. In this approach, a small donor eye limbal biopsy is placed as an explant onto a biocompatible substrate (preferably human amniotic membrane) for expansion. The outgrowth (cultivated limbal epithelial cells) is then surgically transferred to the recipient eye. Due to changing regulations concerning cell-based therapy, the implementation of cultivated limbal epithelial transplantation in accordance with Good Laboratory Practice using xenobiotic-free systems is becoming widely accepted both in Turkey and worldwide.

Neuroprotective Effects of Eexenatide in a Rotenone-Induced Rat Model of Parkinson's Disease.

BACKROUND: Several studies suggest an association between Parkinson's disease (PD) and type 2 diabetes mellitus; these 2 diseases are both known to affect the common molecular pathways. As a synthetic agonist for the glucagon-like peptide 1 receptor, exenatide has been evaluated as a neuroprotective agent in multiple animal models. Rotenone models of PD have great potential for the investigation of PD pathology and motor and nonmotor symptoms, as well as the role of gene-environment interactions in PD causation and pathogenesis. Therefore, in this study, the neurochemical, behavioral and histologic effects of exenatide on a rotenone-induced rat model of PD were examined. MATERIALS AND METHODS: Eighteen adult male rats were randomly divided into the following 3 groups (n = 6): 1 group received stereotaxical infusion of dimethyl sulfoxide (vehicle, group 1) and the others received stereotaxical infusion of rotenone (groups 2 and 3). Apomorphine-induced rotation test was applied to the rats after 10 days. Thereafter, group 2 was administered isotonic saline, whereas group 3 was administered exenatide for 28 days. RESULTS: Malondialdehyde and tumor necrosis factor alpha levels increased in the rats with PD induced by rotenone, whereas malondialdehyde and tumor necrosis factor alpha levels markedly decreased in the rats treated with exenatide. The apomorphine-induced rotation test scores of exenatide-treated rats were determined to be lower compared with the untreated group. Additionally, treatment with exenatide significantly reduced the loss of dopaminergic neurons in striatum. CONCLUSIONS: These results have shown that exenatide has neuroprotective, anti-inflammatory and antioxidant effects in a rotenone-induced rat model of PD.

Beneficial effects of agomelatine in experimental model of sepsis-related acute kidney injury.

BACKGROUND: Sepsis-related acute kidney injury (AKI) is a serious complication of sepsis. Problems persist regarding early diagnosis and treatment of AKI. The aim of the present study was to evaluate the efficacy of agomelatine, which is primarily known for its positive effects on depressive and anxiety disorders in sepsis-related AKI. METHODS: Sepsis model was created with cecal ligation puncture (CLP). Rats were separated into 4 groups of 8 each: the control group, the sham-operated group, the CLP+saline group, and the CLP+agomelatine group. Agomelatine was administered intraperitoneally in doses of 20 mg/kg. RESULTS: In the agomelatine group, reductions were observed in levels of tumor necrosis factor α (TNF-α), malondialdehyde (MDA), blood urea nitrogen (BUN), and creatinine, as well as in histological kidney scores, compared to the non-treated group. In addition, it was demonstrated that agomelatine treatment had positive effect on sepsis-induced morphological damage to renal and tubular tissues. CONCLUSION: Agomelatine showed strong efficacy in sepsis-related AKI, demonstrated with histological and biochemical results in an experimental model. It is believed that antioxidant and pro-inflammatory effects of agomelatine are responsible for the improvement in kidneys.

Impact of aortic cross-clamping time on peripheral nerves: experimental model.

PURPOSE: The present study investigated the correlation between extend aortic cross-clamping time and peripheral nerve injury on rats. METHODS: 24 male, Sprague Dawley rats were divided into 3 groups; (a) control group: abdomen was directly closed after reached aorta, and followed by 72 hours, (b) short-term ischaemia-reperfusion group: peripheral nerve ischemia was induced in rats by supraceliac aortic occlusion for 20 min followed by 72 h of reperfusion, (c) long-term ischaemia-reperfusion group: peripheral nerve ischemia was induced for 30 min followed by 72 h of reperfusion. Preoperative and postoperative, electromyography (EMG) recordings were done. End of 72 h, the sciatic nerves were harvested from each animal for histopathological and biochemical analysis. RESULTS: The mean compound muscle action potential (CMAP) amplitude of long-term ischaemia-reperfusion group was statically significant reduced when compared to the control group (p <0.01). However, the mean distal latency value of long-term ischaemia-reperfusion group was statically significant increased (p <0.01). On the other hand, there were statically significant differences between the results of malondialdehyde, edema and ischemia fiber degeneration grades on control and long-term ischaemia-reperfusion group (p <0.001). CONCLUSION: This study demonstrated that the extending cross clamping time directly harms the peripheral nerve of rats.

The neuroprotective effect of erythropoietin on experimental Parkinson model in rats.

Dopaminergic neuronal loss in Parkinson's disease (PD) results from oxidative stress, neuroinflammation and excitotoxicity. Because erythropoietin (EPO) has been shown to have antioxidant, anti-inflammatory and neuroprotective effects in many previous studies, present study was designed to evaluate the effect of EPO on rotenone-induced dopaminergic neuronal loss. The rats in which PD was induced by stereotaxical infusion of rotenone showed increased MDA and TNF-alpha levels and decreased HVA levels. On the other hand, EPO treatment resulted in markedly decreased MDA and TNF-alpha levels and increased HVA levels. EPO treatment in rotenone-infusion group resulted in improvement of striatal neurodegeneration and a significant increase in decreased total number of neurons and immunohistochemical TH positive neurons. Results of the present study demonstrate the neuroprotective, anti-inflammatory and antioxidant effects of EPO in a rotenone-induced neurodegenerative animal model.

Regression of experimental endometriotic implants in a rat model with the angiotensin II receptor blocker losartan.

AIM: Endometriosis is a common disease in women of reproductive age, and many different treatments have been developed, although none has provided a cure. In this study, the efficacy of losartan, an angiotensin II type 1 receptor blocker and an antiangiogenic and anti-inflammatory agent, on regression of experimental endometriotic implants in a rat model was investigated. METHODS: Peritoneal endometriosis was surgically induced in 16 mature female Sprague-Dawley rats. The peritoneal endometriotic implant was confirmed after 28 days, and the animals were divided randomly into two groups. The control group (n = 8) was given 4 mL/day tap water by oral gavage, and the losartan group (n = 8) was given 20 mg/kg per day losartan p.o. We compared endometriotic implant size, extent and severity of adhesion, as well as plasma and peritoneal lavage fluid cytokine levels including vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-α, plasma inflammatory factor pentraxin-3 (PTX-3) and C-reactive protein (CRP) between the treatment groups. RESULTS: Mean surface endometriotic area, histological score of implants, adhesion formation, plasma VEGF, TNF, PTX-3 and CRP levels were significantly lower in the losartan group compared with control (P < 0.05). Furthermore, the peritoneal VEGF level was lower in the losartan group than in the control group (P < 0.001), but peritoneal TNF-α was similar in both groups (P > 0.05). CONCLUSION: Losartan suppressed the implant surface area of experimental endometriosis in rats and reduced the levels of plasma VEGF, TNF-α, PTX-3 and CRP.

Experimental comparison of protective characteristics of enalapril and trimetazidine in diabetic nephropathy.

Abstract Hyperglycemia, hypertension, dyslipidemia, and inflammation have been proposed to account for the development of nephropathy in diabetic subjects. The beneficial effects of enalapril on diabetic nephropathy are known. However, the effects of trimetazidine (TMZ) are still unknown. We aimed at comparing the effects of the enalapril and TMZ treatment on fibronectin expression, inducible nitric oxide synthase expression, urine proteinuria, blood glucose and glomerular, and mesangial structures of kidney in rats that take streptozotocin (STZ). In this study, 32 male Sprague-Dawley albino mature rats of 8 weeks, weighing 200-220 g were used. Diabetes was induced by intraperitoneal injection of STZ (60 mg/kg) for 24 rats. We made four groups (Group 1: control, non-diabetic rats (n = 8), Group 2: diabetes, without treatment (n = 8), Group 3: diabetes treatment with enalapril (n = 8), Group 4: diabetes treatment with TMZ (n = 8). The positive effects of renal tissue and tubules in the mesangium immunohistochemical were shown in TMZ receiving rat groups. These positive effects were in parallel with the reduction in fibronectin and I-NOS expression and reduction in the proteinuria. TMZ and enalapril treatment of diabetic rats and renal parenchyma in this study are shown to have positive effects on the different levels.

The effects of different intraabdominal pressure protocols in laparoscopic procedures on oxidative stress markers and morphology in rat ovaries.

BACKGROUND: To determine the effects of different intraabdominal pressure (IAP) on the ovaries in a laparoscopic rat model. OBJECTIVES: The aim of the study was to determine the effects on the ovaries of different intraabdominal pressures (IAP) in laparoscopic surgery in a rat model. MATERIAL AND METHODS: Thirty-two post-pubertal nonpregnant Sprague-Dawley rats were divided randomly into four groups. In the control group, no intraabdominal pressure (IAP) was applied. In Group Pp10 and Group Pp15, an IAP of 10 and 15 mm Hg, respectively, were applied by carbon dioxide insufflation for 60 min, and a 30-min desufflation was carried out. In Group IPp15, a 15 mm Hg IAP was applied for 10 min, and then CO2 was desufflated for 10 min. After this ischemic preconditioning, IAP was established at 15 mm Hg for 60 min, after which CO2 was desufflated for 30 min. Erythrocyte and ovarian tissue malondialdehyde (MDA) and histopathologic damage scores were evaluated. RESULTS: In Groups Pp10 and Pp15, ovarian tissue MDA values were significantly increased compared to the control group. In Groups Pp10 and Pp15, erythrocyte MDA values were significantly increased when compared to Group IPp15 and the control group. Ovarian histopatological assesment scores were significantly higher in Group Pp15 than in Groups Pp10 and IPp15. CONCLUSIONS: Pneumoperitoneum causes injuries to abdominal organ such as the ovaries. The ischemic preconditioning method is more effective in reducing oxidative stress due to laparoscopic pneumoperitoneum than low-pressure pneumoperitoneum methods.

The effect of melatonin on a dorsal skin flap model.

BACKGROUND: Melatonin (Mel) has a very potent antioxidant activity, depending mainly on its capacity to act as an electron donor. Recently, the antioxidant property of Mel has been much emphasized. In this study, the dorsal skin flap model was used to investigate the effect of Mel in flap viability in rats. MATERIAL AND METHODS: Totally 28 Wistar Albino rats were divided into four groups: control group (C) (n = 7), local treatment group (L) (n = 7), systemic low-dose melatonin treatment group (LT) (n = 7), and systemic high-dose melatonin treatment group (HT) (n = 7). The necrosis rate of the skin flaps was observed seven days after the operation by a blinded observer. Oxidative stress was assessed by determining malondialdehyde (MDA) level, and effects of melatonin on antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) were measured. Vascularity, epithelial thickness, and fibroblast proliferation of dorsal skin flaps were assessed histologically. RESULTS: Amount of MDA were found significantly lower (p < .05), and the flap viability, CAT, SOD, vascularity, fibroblast proliferation, and epithelial thickness were found significantly higher (p < .05) in groups HT than in groups C, L, and LT statistically. CONCLUSION: Our results showed that the usage on different doses of melatonin could play an important role in the process of flap viability and further studies will focus on these areas of interest.

Investigation of maternal melatonin effect on the hippocampal formation of newborn rat model of intrauterine cortical dysplasia.

OBJECTIVES: Cortical dysplasia is a cortical malformation resulting from any developmental defects during different periods of development. This study aims to investigate the hippocampal histopathological alterations in the neonates with cortical dysplasia due to the prenatal exposure to carmustine (1,3-bis (2-chloroethyl)-1-nitrosourea; BCNU) and the possible effects of prophylaxis with melatonin, a neuroprotective agent. METHODS: Wistar albino female rats were randomly divided into four experimental groups; control, melatonin-treated, BCNU-exposed and BCNU-exposed+melatonin-treated. Light microscopy and immunohistochemistry were carried out on the newborn hippocampus. RESULTS: Histopathology of hippocampus from the control and melatonin-treated groups showed continuity of migration and maturation as pathognomonic signs of the normal newborn hippocampus. Hippocampal cortex from the newborns exposed in utero to BCNU showed the histology of early embryonic hippocampal formation with immunohistochemical increase in the number of nestin positive cells and decreases in the immunoreactivity of glial fibrillary acidic protein (GFAP) and synaptophysin. These findings indicate a significant delay in hippocampal maturation, migration, and synaptogenesis. Intrauterine treatment of BCNU-exposed rats with melatonin resulted in histopathological features almost similar to control group. CONCLUSION: It has been concluded that cortical dysplasia induced by intrauterine BCNU administration results in delayed hippocampal maturation, which is successfully restored by intrauterine melatonin treatment.

Effects of 2,4-dichlorophenoxyacetic acid formulation on medulla spinalis of Poecilia reticulata: a histopathological study.

This study investigated the possible effects of a commonly used foliar herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) formulation on medulla spinalis of lebistes. Fish were exposed to 2,4-D (15, 30, 45 mg L(-1)), behavioral changes were monitored. Fish were fixed, histopathological examination was carried out on sections taken from the upper parts of the fish body. Histopathology showed increase in neuronal loss, swelling indicating formation of intracellular edema, vacuolization noticed as the formation of vacuoles within or adjacent to cells, deformation in the Nissl granules, pyknosis and gliosis in medulla spinalis. Behavioral changes were decreased general activity, grouping, shortness in breath, sudden rotations and jumping, loss of equilibrium and colour. In conclusion, this commercial formulation of 2,4-D is considerably neurotoxic to lebistes. Fish constitute the last link in the chain of the feeding cycle in aquatic eco-system, number of studies investigating acute and chronic neurotoxicity of various herbicides in fish should be increased.

Immunohistochemical and histopathological evaluation of 2,4-dichlorophenoxyacetic acid-induced changes in rat kidney cortex.

This study aims to investigate the effect of 2,4-dichlorophenoxyacetic acid (2,4-D) on rat kidney cortex histology. Oral exposure of rats to 2,4-D for 28 days resulted in decreases in body weight gain and kidney weight. Histological examination showed degeneration in renal corpuscles and podocytes; vacuolization in the glomerulus with disintegration of the basal membrane; tissue edema; vacuolization, cystic dilation and invagination of the basal laminae in the tubular structures; dilation and congestion in renal corpuscular vessels and marked decrease in glomerular and stromal fibronectin reaction; suggesting that subacute 2,4-D administration induces dose-dependent histopathological degenerative effects in rat kidney cortex.