Structural and ultrastructural changes in the skeletal muscles of dysferlin-deficient mice during postnatal ontogenesis

A number of sarcolemma proteins are responsible for muscle fiber repair. Dysferlin encoded by the DYSF gene is one of these proteins. Dysferlin promotes membrane repair in striated muscle fibers (MFs). Mutations in DYSF lead to loss of or decreased dysferlin expression, impaired membrane repair in MF, and its destruction, clinically manifesting as dysferlinopathy. Preclinical studies of cell and gene therapies aimed at restoring impaired muscle regeneration require well-characterized small animal models. Our investigation aimed to distinguish the histopathological features of a mouse strain lacking dysferlin expression (Bla/J strain). Ultrastructural changes in the sarcolemma, mitochondria and contractile apparatus were observed. It was shown that postnatal histogenesis of skeletal muscles in genetically determined dysferlin deficiency is characterized by a higher proportion of necrotic muscle fibers, compensatory hypertrophy of muscle fibers with their subsequent atrophy, and decreases in proliferative activity and the level of myogenic differentiation of myogenic progenitor cells compared to wild-type mice (C57Bl/6).

[Pathohistological characteristics of muscles in patients with chronic lower limb ischemia]

Despite the widespread occurrence of ischemic diseases of the lower extremities, including atherosclerosis and diseases with an autoimmune component of their pathogenesis, the pathohistological signs of damage and concomitant chronic ischemia, compensatory tissue responses as intracellular and cellular regeneration remain out of the field of vision in researchers.

OBJECTIVE

To assess the signs of damage (the extent of necrosis and apoptosis, capillary density (CD)) and regeneration (the cross-sectional muscle fiber area (CSMFA), the proportion of centrinucleated muscle fibers (CNMFs), and that of connective tissue), by using the gastrocnemius medial head biopsy specimens obtained from patients with heterogeneous forms of chronic lower limb obliterating diseases (CLLODs).

SUBJECTS AND METHODS

The investigation included the biopsy specimens obtained from 44 men under 65 years of age (their mean age was 54±9.8 years) with Stage IIB-IV chronic limb ischemia (according to the A.V. Pokrovsky-Fontaine classification) with its history of at least six months. The nosological entities were atherosclerotic lesion in 33 patients (distal atherosclerosis n=13), multistage lesion (n=8), and Leriche's syndrome (n=12); autoimmune-mediated vascular injury in 11 patients (Buerger's disease (n=7) and nonspecific aortoarteritis (n=4)). The similar muscle fragments obtained during autopsy from the deceased without obvious signs of cardiovascular system diseases were examined as a control.

RESULTS

It was found that there was a statistically significant difference between the nosological entities, as compared to the control in terms of CD and CSMFA (a decrease), the proportion of CNMFs and that of connective tissue (an increase). No substantial differences were found in the studied parameters between the nosological entities.

CONCLUSION

The findings may suggest the universal mechanism for damage to striated muscle tissue because of circulatory hypoxia, regardless of its etiology and the common character of tissue compensatory-adaptive responses (regeneration).

Proangiogenic Effect of 2A-Peptide Based Multicistronic Recombinant Constructs Encoding VEGF and FGF2 Growth Factors

Coronary artery disease remains one of the primary healthcare problems due to the high cost of treatment, increased number of patients, poor clinical outcomes, and lack of effective therapy. Though pharmacological and surgical treatments positively affect symptoms and arrest the disease progression, they generally exhibit a limited effect on the disease outcome. The development of alternative therapeutic approaches towards ischemic disease treatment, especially of decompensated forms, is therefore relevant. Therapeutic angiogenesis, stimulated by various cytokines, chemokines, and growth factors, provides the possibility of restoring functional blood flow in ischemic tissues, thereby ensuring the regeneration of the damaged area. In the current study, based on the clinically approved plasmid vector pVax1, multigenic constructs were developed encoding vascular endothelial growth factor (VEGF), fibroblast growth factors (FGF2), and the DsRed fluorescent protein, integrated via picornaviruses' furin-2A peptide sequences. In vitro experiments demonstrated that genetically modified cells with engineered plasmid constructs expressed the target proteins. Overexpression of VEGF and FGF2 resulted in increased levels of the recombinant proteins. Concomitantly, these did not lead to a significant shift in the general secretory profile of modified HEK293T cells. Simultaneously, the secretome of genetically modified cells showed significant stimulating effects on the formation of capillary-like structures by HUVEC (endothelial cells) in vitro. Our results revealed that when the multicistronic multigene vectors encoding 2A peptide sequences are created, transient transgene co-expression is ensured. The results obtained indicated the mutual synergistic effects of the growth factors VEGF and FGF2 on the proliferation of endothelial cells in vitro. Thus, recombinant multicistronic multigenic constructs might serve as a promising approach for establishing safe and effective systems to treat ischemic diseases.

Early ultra- and microstructural alterations in rat pancreas in alloxan-induced diabetes mellitus

An adequate experimental model is important to understand pathophysiological processes ongoing in the pancreas with diabetes mellitus. Our study was aimed to describe early ultra- and microstructural changes in the rat pancreas in 12-48 h after alloxan administration in a dose of 180 mg/kg. A histopathological examination of the endocrine pancreas revealed the loss of borders between endocrine cells, granular dystrophy and degranulation, sings of necrosis in central cells of the Langerhans islets and apoptosis of their peripheral ones manifested as DNA fragmentation and an increased expression of apoptosis markers. There was a gradual increase of a Langerhans islet area, a decreased percentage of insulin+ cells and an increased one of glucagon+ cells, as well as the presence of proliferating islet cells were found. Structural changes of the exocrine pancreas included fatty degeneration, signs of exocrine cell mitochondrial damage, increased acini, which are located mainly around the Langerhans islets, as well as perivascular edema and leukocytic infiltration. Described ultra- and microstructural alterations suggest a significant contribution of apoptosis to death of endocrine cells exposed to alloxan. Coexisting damage of the exocrine pancreas with its stroma involvement is for the first time described.

Quantitative changes in perineuronal nets in development and posttraumatic condition

Perineuronal net (PNN) is a highly structured portion of the CNS extracellular matrix (ECM) regulating synaptic plasticity and a range of pathologic conditions including posttraumatic regeneration and epilepsy. Here we studied Wisteria floribunda agglutinin-stained histological sections to quantify the PNN size and enrichment of chondroitin sulfates in mouse brain and spinal cord. Somatosensory cortex sections were examined during the period of PNN establishment at postnatal days 14, 21 and 28. The single cell PNN size and the chondroitin sulfate intensity were quantified for all cortex layers and specifically for the cortical layer IV which has the highest density of PNN-positive neurons. We demonstrate that the chondroitin sulfate proteoglycan staining intensity is increased between P14 and P28 while the PNN size remains unchanged. We then addressed posttraumatic changes of the PNN expression in laminae 6 and 7 of cervical spinal cord following hemisection injury. We demonstrate increase of the chondroitin sulfate content at 1.6-1.8 mm rostrally from the injury site and increase of the density of PNN-bearing cells at 0.4-1.2 mm caudally from the injury site. We further demonstrate decrease of the single cell PNN area at 0.2 mm caudally from the injury site suggesting that the PNN ECM takes part in the posttraumatic tissue rearrangement in the spinal cord. Our results demonstrate new insights on the PNN structure dynamics in the developing and posttraumatic CNS.

Gene Therapy Using Plasmid DNA Encoding VEGF164 and FGF2 Genes: A Novel Treatment of Naturally Occurring Tendinitis and Desmitis in Horses

This clinical study describes the intralesional application of the plasmid DNA encoding two therapeutic species-specific growth factors: vascular endothelial growth factor (VEGF164) and fibroblast growth factor 2 (FGF2) in seven horses to restore naturally occurring injuries of the superficial digital flexor tendon (SDFT) (tendinitis) and in three horses with suspensory ligament branch desmitis. Following application all horses were able to commence a more rapid exercise program in comparison to standardized exercise programs. Clinical observation and ultrasonic imaging was used to evaluate the regeneration rate of the tendon and ligament injury recovery and to confirm the safety of this gene therapy in horses, throughout a 12 month period. Follow-up data of the horses revealed a positive outcome including significant ultrasonographic and clinical improvements in 8 out of 10 horses with SDFT and suspensory ligament branch lesions, with return to their pre-injury level of performance by 2–6 months after the completion of treatment. The ninth horse initially presenting with severe suspensory ligament branch desmopathy, showed no significant ultrasonographic improvements in the first 2 months after treatment, however, it improved clinically and became less lame. The final horse, presenting with severe tendinitis of the SDFT returned to their pre-injury level of performance, but experienced re-injury 6 months after treatment. This data is highly promising, however, further research in experimental models, with the histopathological, immunohistochemical and gene expression evaluation of the equine tendon/ligament after gene therapy application is required in order to fully understand the mechanisms of action. This treatment and the significant clinical impacts observed represents an important advancement in the field of medicine.

Transcriptional Analysis of Blood Lymphocytes and Skin Fibroblasts, Keratinocytes, and Endothelial Cells as a Potential Biomarker for Alzheimer's Disease

Alzheimer's disease (AD) is a devastating and progressive form of dementia that is typically associated with a build-up of amyloid-β plaques and hyperphosphorylated and misfolded tau protein in the brain. Presently, there is no single test that confirms AD; therefore, a definitive diagnosis is only made after a comprehensive medical evaluation, which includes medical history, cognitive tests, and a neurological examination and/or brain imaging. Additionally, the protracted prodromal phase of the disease makes selection of control subjects for clinical trials challenging. In this study we have utilized a gene-expression array to screen blood and skin punch biopsy (fibroblasts, keratinocytes, and endothelial cells) for transcriptional differences that may lead to a greater understanding of AD as well as identify potential biomarkers. Our analysis identified 129 differentially expressed genes from blood of dementia cases when compared to healthy individuals, and four differentially expressed punch biopsy genes between AD subjects and controls. Additionally, we identified a set of genes in both tissue compartments that showed transcriptional variation in AD but were largely stable in controls. The translational products of these variable genes are involved in the maintenance of the Golgi structure, regulation of lipid metabolism, DNA repair, and chromatin remodeling. Our analysis potentially identifies specific genes in both tissue compartments that may ultimately lead to useful biomarkers and may provide new insight into the pathophysiology of AD.

Gene Therapy Using Plasmid DNA Encoding Vascular Endothelial Growth Factor 164 and Fibroblast Growth Factor 2 Genes for the Treatment of Horse Tendinitis and Desmitis: Case Reports

In this clinical study, for the first time we used the direct gene therapy to restore severe injuries of the suspensory ligament branch and superficial digital flexor tendon in horses (Equus caballus). We injected the plasmid DNA encoding two therapeutic species-specific growth factors: vascular endothelial growth factor 164 and fibroblast growth factor 2 at the site of injury in the suspensory ligament branch and tendon. Treatment effects were evaluated with the use of clinical observation and ultrasound imaging during a period of a few months. We showed that gene therapy used within a period of 2–3 months after the injury resulted in the complete recovery of functions and full restoration of the severely damaged suspensory ligament and superficial digital flexor tendon.

Cytochalasin B-induced membrane vesicles convey angiogenic activity of parental cells

Naturally occurring extracellular vesicles (EVs) play essential roles in intracellular communication and delivery of bioactive molecules. Therefore it has been suggested that EVs could be used for delivery of therapeutics. However, to date the therapeutic application of EVs has been limited by number of factors, including limited yield and full understanding of their biological activities. To address these issues, we analyzed the morphology, molecular composition, fusion capacity and biological activity of Cytochalasin B-induced membrane vesicles (CIMVs). The size of these vesicles was comparable to that of naturally occurring EVs. In addition, we have shown that CIMVs from human SH-SY5Y cells contain elevated levels of VEGF as compared to the parental cells, and stimulate angiogenesis in vitro and in vivo.

Spatial patterns and cell surface clusters in perineuronal nets

Perineuronal nets (PNN) ensheath GABAergic and glutamatergic synapses on neuronal cell surface in the central nervous system (CNS), have neuroprotective effect in animal models of Alzheimer disease and regulate synaptic plasticity during development and regeneration. Crucial insights were obtained recently concerning molecular composition and physiological importance of PNN but the microstructure of the network remains largely unstudied. Here we used histochemistry, fluorescent microscopy and quantitative image analysis to study the PNN structure in adult mouse and rat neurons from layers IV and VI of the somatosensory cortex. Vast majority of meshes have quadrangle, pentagon or hexagon shape with mean mesh area of 1.29µm(2) in mouse and 1.44µm(2) in rat neurons. We demonstrate two distinct patterns of chondroitin sulfate distribution within a single mesh - with uniform (nonpolar) and node-enriched (polar) distribution of the Wisteria floribunda agglutinin-positive signal. Vertices of the node-enriched pattern match better with local maxima of chondroitin sulfate density as compared to the uniform pattern. PNN is organized into clusters of meshes with distinct morphologies on the neuronal cell surface. Our findings suggest the role for the PNN microstructure in the synaptic transduction and plasticity.

Improved cognitive, affective and anxiety measures in patients with chronic systemic disorders following structured physical activity

Mental illnesses are frequent co-morbid conditions in chronic systemic diseases. High incidences of depression, anxiety and cognitive impairment complicate cardiovascular and metabolic disorders such as hypertension and diabetes mellitus. Lifestyle changes including regular exercise have been advocated to reduce blood pressure and improve glycaemic control. The purpose of this project was to evaluate the effect of physical training on the most prevalent corollary psychiatric problems in patients with chronic organic ailments. This longitudinal study assessed the mental health of hypertensive (age: 57 ± 8 years) and/or diabetic (age: 53 ± 8 years) patients using mini-mental state examination, Beck's depression inventory, Beck's anxiety inventory and self-reporting questionnaire-20 before and after a 3-month supervised resistance and aerobic exercise programme comprising structured physical activity three times a week. Clinically relevant improvement was observed in the Beck's depression inventory and Beck's anxiety inventory scores following the 12-week training (61%, p = 0.001, and 53%, p = 0.02, respectively). Even though statistically not significant (p = 0.398), the cognitive performance of this relatively young patient population also benefited from the programme. These results demonstrate positive effects of active lifestyle on non-psychotic mental disorders in patients with chronic systemic diseases, recommending exercise as an alternative treatment option.

Construction of recombinant adenovirus containing picorna-viral 2A-peptide sequence for the co-expression of neuro-protective growth factors in human umbilical cord blood cells

STUDY DESIGN

Experimental study.

OBJECTIVE

Several neuro-degenerative disorders such as Alzheimer's dementia, Parkinson's disease and amyotrophic lateral sclerosis (ALS) are associated with genetic mutations, and replacing or disrupting defective sequences might offer therapeutic benefits. Single gene delivery has so far failed to achieve significant clinical improvements in humans, leading to the advent of co-expression of multiple therapeutic genes. Co-transfection using two or more individual constructs might inadvertently result in disproportionate delivery of the products into the cells. To prevent this, and in order to rule out interference among the many promoters with varying strength, expressing multiple proteins in equimolar amounts can be achieved by linking open reading frames under the control of only one promoter.

SETTING

Kazan, Russian Federation.

METHODS

Here we describe a strategy for adeno-viral co-expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor 2 (FGF2) interconnected through picorna-viral 2A-amino-acid sequence in transfected human umbilical cord blood mono-nuclear cells (hUCB-MCs).

RESULTS

Presence of both growth factors, as well as absence of immune response to 2A-antigen, was demonstrated after 28-52 days. Following injection of hUCB-MCs into ALS transgenic mice, co-expression of VEGF and FGF2, as well as viable xeno-transplanted cells, were observed in the spinal cord after 1 month.

CONCLUSION

These results suggest that recombinant adeno-virus containing 2A-sequences could serve as a promising alternative in regenerative medicine for the delivery of therapeutic molecules to treat neurodegenerative diseases, such as ALS.

Analysis of the efficiency of gene-cell therapy in transgenic mice with amyotrophic lateral sclerosis phenotype

Amyotrophic lateral sclerosis is a neurodegenerative disease characterized by progressive death of cerebral and spinal motorneurons. Using behavioral tests we studied the efficiency of gene-cell therapy in SOD1 G93A transgenic mice receiving xenotransplantation of human umbilical cord blood mononuclear cells genetically modified with adenoviral vectors encoding vascular endothelial growth factor (VEGF) and reporter green fluorescent protein (EGFP) genes. The cells were transplanted to mice on week 27 of life (preclinical stage of the disease). Behavioral tests (open field, grip strength test) showed that transplantation of umbilical cord blood mononuclear cells expressing VEGF significantly improved the parameters of motor and explorative activity, grip strength, and animal survival. Thus, gene-cell therapy based on genetically modified mononuclear cells expressing VEGF can be efficient for the treatment of amyotrophic lateral sclerosis.

Expression of P2X receptor subtypes on CD34+ cells and c-kit+ cells of human umbilical blood

The presence of several subtypes of P2X receptors on early hemopoietic precursors (CD34+) from human umbilical blood was detected by flow cytometry. The expression of P2X receptors on umbilical blood lymphocytes was an order of magnitude higher than that on adult human blood cells. Our results attest to early involvement of P2X receptors in differentiation of human hemopoietic cells.

A direct technique for magnetic functionalization of living human cells

Functionalized living cells are regarded as effective tools in directed cell delivery and tissue engineering. Here we report the facile functionalization of viable isolated HeLa cells with superparamagnetic cationic nanoparticles via a single-step biocompatible process. Nanoparticles are localized on the cellular membranes and do not penetrate into the cytoplasm. The magnetically responsive cells are viable and able to colonize and grow on substrates. Magnetically facilitated microorganization of functionalized cells into viable living clusters is demonstrated. We believe that the technique described here may find a number of potential applications in cell-based therapies and in development of whole-cell biosensors.

Genetically modified human umbilical cord blood cells expressing vascular endothelial growth factor and fibroblast growth factor 2 differentiate into glial cells after transplantation into amyotrophic lateral sclerosis transgenic mice

Current therapy of a number of neuropsychiatric maladies has only symptomatic modality. Effective treatment of these neuro-degenerative diseases, including amyotrophic lateral sclerosis (ALS), may benefit from combined gene/stem-cell approaches. In this report, mononuclear fraction of human umbilical cord blood cells (hUCBCs) were transfected by electroporation with dual plasmid constructs, simultaneously expressing vascular endothelial growth factor 165 (VEGF(165)) and human fibroblast growth factor 2 (FGF(2)) (pBud-VEGF-FGF(2)). These genetically modified hUCBCs were injected retro-orbitally into presymptomatic ALS transgenic animal models ((G)93(A) mice). Lumbar spinal cords of rodents were processed for immunofluoresent staining with antibodies against human nuclear antigen (HNA), oligodendrocyte-specific protein, S100, iba1, neuronal β(3)-tubulin and CD34. Co-localization of HNA and S100 was found in the spinal cord of mice after transplantation of genetically modified hUCBCs over-expressing VEGF-FGF(2). Double staining in control animals treated with unmodified hUCBCs, however, revealed HNA+ cells expressing iba1 and CD34. Neuron-specific β(3)-tubulin or oligodendrocyte-specific protein were not expressed in hUCBCs in either control or experimental mice. These results demonstrate that genetically naïve hUCBCs may differentiate into endothelial (CD34+) and microglial (iba1+) cells; however when over-expressing VEGF-FGF(2), hUCBCs transform into astrocytes (S100+). Autocrine regulation of VEGF and FGF(2) on hUCBCs, signal molecules from dying motor neurons in spinal cord, as well as self-differentiating potential may provide a unique microenvironment for the transformation of hUCBCs into astrocytes that eventually serve as a source of growth factors to enhance the survive potential of surrounding cells in the diseased regions.

Human tooth germ stem cells preserve neuro-protective effects after long-term cryo-preservation

The use of mesenchymal stem cells (MSCs) has been shown to be promising in chronic disorders such as diabetes, Alzheimer's dementia, Parkinson's disease, spinal cord injury and brain ischemia. Recent studies revealed that human tooth germs (hTG) contain MSCs which can be easily isolated, expanded and cryo-preserved. In this report, we isolated human tooth germ stem cells (hTGSCs) with MSC characteristics from third molar tooth germs, cryo-preserved them at -80( degrees )C for 6 months, and evaluated for their surface antigens, expression of pluri-potency associated genes, differentiation capacity, karyotype, and proliferation rate. These characteristics were compared to their non-frozen counterparts. In addition, neuro-protective effects of cryo-preserved cells on neuro-blastoma SH-SY5Y cells were also assessed after exposure to stress conditions induced by hydrogen-peroxide (oxidative stress) and paclitaxel (microtubule stabilizing mitotic inhibitor). After long term cryo-preservation hTGSCs expressed surface antigens CD29, CD73, CD90, CD105, and CD166, but not CD34, CD45 or CD133, which was typical for non-frozen hTGSCs. Cryo-preserved hTGSCs were able to differentiate into osteo-, adipo- and neuro-genic cells. They also showed normal karyotype after high number of population doublings and unchanged proliferation rate. On the other hand, cryo-preserved cells demonstrated a tendency for lower level of pluri-potency associated gene expression (nanog, oct4, sox2, klf4, c-myc) than non-frozen hTGSCs. hTGSCs conditioned media increased survival of SH-SY5Y cells exposed to oxidative stress or paclitaxel. These findings confirm that hTGSCs preserve their major characteristics and exert neuro-protection after long-term cryo-preservation, suggesting that hTGSCs, harvested from young individuals and stored for possible use later as they grow old, might be employed in cellular therapy of age-related degenerative disorders.

Human umbilical cord blood cells transfected with VEGF and L(1)CAM do not differentiate into neurons but transform into vascular endothelial cells and secrete neuro-trophic factors to support neuro-genesis-a novel approach in stem cell therapy

Genetically modified mono-nuclear cell fraction from human umbilical cord blood (HUCB) expressing human vascular endothelial growth factor (VEGF) and mouse neural L(1) cell adhesion molecule (L(1)CAM) were used for gene-stem cell therapy of transgenic (G)93(A) mice adopted as an animal amyotrophic lateral sclerosis (ALS) model. We generated non-viral plasmid constructs, expressing human VEGF(165) (pcDNA-VEGF) and mouse neural L(1) cell adhesion molecule (pcDNA-mL(1)CAM). Mono-nuclear fraction of HUCB cells were transiently transfected by electro-poration with a mixture of expression plasmids (pcDNA-VEGF+pcDNA-mL(1)CAM). Sixteen transgenic female and male mice were randomly assigned to three groups: (1) transplantation of genetically modified HUCB cells expressing L(1) and VEGF (n=6), (2) transplantation of un-transfected HUCB cells (n=5), and (3) control group (n=5). In first two experimental groups 1x10(6) cells were injected retro-orbitally in pre-symptomatic 22-25-week-old (G)93(A) mice. Our results demonstrate that HUCB cells successfully grafted into nervous tissue of ALS mice and survived for over 3 months. Therefore, genetically modified HUCB cells migrate in the spinal cord parenchyma, proliferate, but instead of transforming into nerve cells, they differentiate into endothelial cells forming new blood vessels. We propose that: (A) expression of mouse neural L(1)CAM is responsible for increased homing and subsequent proliferation of transplanted cells at the site of neuro-degeneration, (B) expression of human VEGF directs HUCB cell differentiation into endothelial cells, and (C) neuro-protective effect may stem from the delivery of various neuro-trophic factors from newly formed blood vessels.

Mesenchymal-epithelial transformation of ito cells in vitro

Cultured pure population of Ito cells isolated from adult rat liver expressed epithelial markers cytokeratin-8, alpha-fetoprotein, and gamma-glutamyl transpeptidase after forming a dense monolayer. Mesenchymal-epithelial transformation of these cells is possible, which suggests them as candidates of hepatic stem cells.

Effect of dimephosphone (monophosphonate) on the course of pregnancy and fetal development in rats

Dimephosphone injected on days 1-19 of gestation did not cause fetal death and specific abnormalities in rats and did not modulate sex differentiation of fetuses. Morphological study of fetal liver revealed no pathological changes.

Alteration of the liver in rats with experimental dysbiosis

We evaluated the relationship between pathological changes in the liver and the state of intestinal microflora in rats with experimental dysbiosis. Changes in the intestinal microflora were accompanied by alteration of the morphological structure in the liver. Enhanced proliferation of Ito cells served as an indirect evidence of damage to the liver. Ito cells did not undergo transformation into myofibroblasts that excluded the possibility of fibrosis.

Changes in the count of pancreatic beta- and alpha-cells and blood glucose level in rats with alloxan-induced diabetes

We estimated the count of pancreatic alpha- and beta-cells and blood glucose level at various stages of alloxan-induced diabetes in rats. Alloxan decreased the count of insulin-producing beta-cells, but increased the number of glucagon-secreting alpha-cells in the pancreas (week 1 of diabetes). These changes were accompanied by hyperglycemia. The decrease in blood glucose level in diabetic rats was associated with an increase in beta-cell count against the background of high density of pancreatic alpha-cells.

A single endotoxin aggression causes dose-dependent reversible activation of rat liver Ito cells without their transdifferentiation into myofibroblasts

The effect of Gram-negative bacterial lipopolysaccharide on rat hepatocytes and sinusoidal cells was studied. The damage and regeneration potential of the liver were evaluated by activation of perisinusoidal Ito cells and proliferative activity of liver cells. Compensatory and repair reactions in the liver induced by lipopolysaccharide manifested by proliferation of liver cells and reversible activation of Ito cells without their transdifferentiation into myofibroblasts.