The protective impact of hesperidin against carbimazole-induced hypothyroidism, via enhancement of inflammatory cytokines, histopathological alterations, and Nrf2/HO-1

The aim of this study was to evaluate the anti-inflammatory, antioxidant, and antiproliferative effects of hesperidin (HSP) and eltroxin (ELT) on hypothyroidism (HPO) induced by carbimazole (CBZ) in white male albino rats. Thirty-two adult rats were categorized into four groups: Group 1, no treatment (control); Group II, treated with CBZ (20 mg/kg); Group III, treated with HSP (200 mg/kg) + CBZ; and Group IV, treated with ELT (0.045 mg/kg) + CBZ. All treatments were provided as oral daily doses for 90 days. Thyroid hypofunction was significantly manifested in Group II. However, increased levels of thyroid hormones, antioxidant enzymes, nuclear factor erythroid 2-related factor 2, heme oxygenase 1, and interleukin (IL)-10, and a decrease in the level of the thyroid-stimulating hormone were observed in Groups III and IV. On the contrary, decreased levels of lipid peroxidation, inducible nitric oxide synthase, tumor necrosis factor α, IL-17, and cyclooxygenase 2 were detected in groups III and IV. The histopathological and ultrastructural findings were ameliorated in Groups III and IV; on the contrary, Group II presented with significant increases in the height and number of layers of the follicular cells. Immunohistochemistry demonstrated a marked increase in thyroglobulin and significant decreases in the levels of nuclear factor kappa B and proliferating cell nuclear antigen in Groups III and IV. These results confirmed the effectiveness of HSP as an anti-inflammatory, antioxidant, and antiproliferative agent in rats with hypothyroidism. Additional studies are required to assess its potential as a novel agent against HPO.

Ultrastructural characteristics of erythroid cells in congenital dyserythropoietic anemia type II, with a focus on peripheral cisternae and double membranes

Peripheral cisternae and double membranes (PCDMs) in erythroid cells are a landmark of type II congenital dyserythropoietic anemia (CDA). To gain further insights into the mechanism of dyserythropoiesis, erythroblasts and erythrocytes in bone marrow were studied in 22 Chinese patients with CDA Ⅱ by transmission electron microscopy. The study demonstrated an increase in all patients in erythroblasts with PCDMs with development from pro-erythroblast to red blood cells. PCDMs often connected with cisternae of endoplasmic reticulum (ER) and the perinuclear space, and were accompanied by karyopyknosis, karyolysis and disruption in polychromatic and orthochromatic erythroblasts. The results suggest that PCDMs are transformed from ER during erythropoiesis and participate in the dissolution and deletion of late erythroid cells in patients with CDA II.

Antimycobacterial compound of chitosan and ethambutol: ultrastructural biological evaluation in vitro against Mycobacterium tuberculosis

Chitosan (CS) is a promising biopolymer and has been tested as a complement to the action and compensation of toxicity presented by anti-tuberculosis drugs. The present work studied the adjuvant effect of CS with the drug ethambutol (EMB) as a compound (CS-EMB), to explore its antimicrobial and cytotoxic activity, using transmission electron microscopy (TEM), to examine ultracellular changes that represent possible antimycobacterial action of CS on Mycobacterium tuberculosis (Mtb). Antimycobacterial activities were tested against reference strains Mtb ATCC® H37Rv and multidrug resistant (MDR). In vitro cytotoxicity tests were performed on Raw 264.7. For the studied compounds, morphological, ultrastructural, and physical-chemical analyses were performed. Drug-polymer interactions that occur through the H bridges were confirmed by physical-chemical analyses. The CS-EMB compound is stable at pHs of 6.5-7.5, allowing its release at physiological pH. The antibacterial activity (minimum inhibitory concentration) of the CS-EMB compound was 50% greater than that of the EMB in the H37Rv and MDR strains and the ultrastructural changes in the bacilli observed by TEM proved that the CS-EMB compound has a bactericidal action, allowing it to break down the Mtb cell wall. The cytotoxicity of CS-EMB was higher than that of isolated EMB, IC50 279, and 176 μg/mL, respectively. It is concluded that CS-EMB forms a promising composite against strains Mtb H37Rv and multidrug resistant (MDR-TB).Key points• Our study will be the first to observe ultrastructurally the effects of the CS-EMB compound on Mtb cells.• CS-EMB antimicrobial activity in a multidrug-resistant clinical strain.• The CS-EMB compound has promising potential for the development of a new drug to fight tuberculosis.

Effect of pile fermentation on the cells of Chinese Liupao tea: The first record of cell wall of Liupao tea on transmission electron microscope

Fermentation often degrades the cell wall of dark tea, changes the carbohydrate components in the cell wall of tea, and thus affects the quality of tea. However, the lack of ultrastructural details limits our knowledge on the effect of fermentation on tea cell walls. Morphological studies of cell structures are important; thus, the cell wall of Liupao tea was analyzed under transmission electron microscopy for the first time, and the effects of different raw materials and fermentation methods on the cell wall and main carbohydrates of tea were compared. Overall, fermentation degrades the cell wall of Liupao tea under the action of microorganisms. Interestingly, the middle lamella degrades obviously, whereas the primary wall is complete. The decrease in hemicellulose and increase in water-soluble pectin (WSP) were remarkable, whereas the changes in cellulose and WSP were considerably correlated with the increase in tea polysaccharide (TPS). The results suggest that cell wall degradation might be related to the increase in TPS.

The in Vitro Antischistosomal Activity and Genotoxicity of the Active Ingredients of Allium sativum (allicin) and Curcuma longa (curcumin)

Background:

In this study, we assessed the in vitro antischistosomal activity of the active ingredients of Allium sativum (allicin) and Curcuma longa (curcumin) on Schistosoma mansoni.

Methods:

This study was conducted in Faculty of Science, Port said University, Egypt (2018). Adult worms were exposed to a range of concentrations of AL or CU, and worm survival was assessed 24 h post-exposure to calculate the lethal concentration of the compounds. Scanning electron microscopy was used to assess ultrastructural changes in the surface of AL- or CU- treated worms. The genotoxicities of AL and CU on S. mansoni were determined by DNA fragmentation analysis.

Results:

We determined the concentrations of AL and CU required to kill 50% of S. mansoni (LC₅₀ ). The LC₅₀ of AL was 8.66 μL/mL, whereas 100% mortality of S. mansoni was achieved by AL at concentrations of 50 μL/mL. The LC₅₀ of CU was 87.25 μL/mL, with the highest mortality of 91.3% seen after 24 h exposure to 100 μg/mL CU. Ultrastructural studies revealed that exposure to either AL or CU led to mild or severe surface damage to S. mansion, respectively. The degree of damage in the worms was sex-dependent. Interestingly, while CU exposure resulted in DNA fragmentation in S. mansoni worms, we observed no genotoxic effects of AL.

Conclusion:

Both AL and CU exhibit antischistosomal activity; the study provided evidence suggesting that these compounds act through distinct mechanisms. These promising results encourage further investigation into these compounds as potential antischistosomal agents, either alone or as complementary treatments to praziquantel.

The neuroprotective role of melatonin in a gestational hypermethioninemia model

Elevated levels of methionine in blood characterize the hypermethioninemia, which may have genetic or non-genetic origin, as for example from high protein diet. Born rats from hypermethioninemic mothers presented cerebral oxidative stress, inhibition of Na⁺,K⁺-ATPase, memory deficit and ultrastructure cerebral changes. Melatonin is a hormone involved in circadian rhythm and has antioxidant effects. The aim of this study was to verify the possible neuroprotective effects of melatonin administration in hypermethioninemic pregnant rats on damage to biomolecules (Na⁺,K⁺-ATPase, sulfhydryl content and DNA damage index) and behavior (open field, novel object recognition and water maze tasks), as well as its effect on cells morphology by electron microscopy in offspring. Wistar female rats received methionine (2.68 μmol/g body weight) and/or melatonin (10 mg/kg body weight) by subcutaneous injections during entire pregnancy. Control rats received saline. Biochemical analyzes were performed at 21 and 30 days of life of offspring and behavioral analyzes were performed only at 30 days of age in male pups. Results showed that gestational hypermethioninemia diminished Na⁺,K⁺-ATPase activity and sulfhydryl content and increased DNA damage at 21 and 30 days of life. Melatonin was able to totally prevent Na⁺,K⁺-ATPase activity alteration at 21 days and partially prevent its alteration at 30 days of rats life. Melatonin was unable in to prevent sulfhydryl and DNA damage at two ages. It also improved DNA damage, but not at level of saline animals (controls). Regarding to behavioral tests, data showed that pups exposed to gestational hypermethioninemia decreased reference memory in water maze, spent more time to the center of the open field and did not differentiate the objects in the recognition test. Melatonin was able to prevent the deficit in novel object recognition task. Electron microscopy revealed ultrastructure alterations in neurons of hypermethioninemic at both ages of offspring, whose were prevented by melatonin. These findings suggest that melatonin may be a good neuroprotective to minimize the harmful effects of gestational hypermethioninemia on offspring.

Skin nodules associated with parasitism with Henneguya sp. (Cnidaria: Myxosporea) in the neotropical fish Cyphocharax modestus

A new myxozoan species, Henneguya sp., is described based on material from skin of Cyphocharax modestus. Mature myxospores are were elongate and ellipsoidal, measuring 21.4 ± 1.2 (19.4-23.2) μm in total length, 5.1 ± 0.3 (4.5-5.8) μm in width, 11.9 ± 0.5 (10.9-12.7) μm in body length and 9.6 ± 0.7 (8.4-10.5) μm in length of the caudal process. The polar capsules were elongated and had unequal sizes, with length of 5.1 ± 0.4 (4.5-6.0) μm and 5.6 ± 0.4 (4.9-6.3) μm for smaller and larger respectively and width of 1.8 ± 0.2 (1.4-2.0) μm. The larger polar capsule had 8 turns in polar filament while the smaller polar capsule had 5 turns in polar filament. The macroscopic analysis revealed the presence of large nodules, which were located before and after the dorsal fin of the hosts. The histopathological analysis showed the development of nodules filled with plasmodia, surrounded by loose connective tissue, developed in the dermis of the skin. Many cysts containing countless spores, as well as free spores, were located in the dermis and hypodermis of the hosts, causing the disorganization of the connective tissue that is responsible for the support. This is the first record of a Henneguya species in C. modestus.

Ameliorative effect of vitamin B12 on seminiferous epithelium of cimetidine-treated rats: a histopathological, immunohistochemical and ultrastructural study

Cimetidine is an H2 receptor antagonist that has an antiandrogenic effect. It intervenes with the conversion of testosterone into estrogen in the Sertoli cells with accompanying testicular structural changes. In the present study, the microscopic and the ultrastructural changes induced by cimetidine and the effect of vitamin B12 as a protective agent on rat testes were studied. Immunoexpression of estrogen receptor β (ERβ) in testes was evaluated. Twenty-four adult male rats were divided into four groups: control, cimetidine-treated, vitamin B12 treated, and combined cimetidine and vitamin B12 treated. The experimental rats were administered with cimetidine and/or vitamin B12 for 52 days. Group II rats showed marked atrophy of the seminiferous tubules with a significant increase in tubular diameter and decrease in the tubular luminal and epithelial areas. Ultrastructure of this group showed irregular Sertoli cells with basal cytoplasmic vacuolation and significantly thickened basement membrane. ERβ immunoexpression was similar to controls. Group III rats showed near normal seminiferous tubular structures with minimal cellular alterations and the immunoreactivity of the testicular sections was very close to normal. However, group IV rats showed markedly immunopositive detached cells, spermatids, and primary spermatocytes. Cimetidine interferes with the control of spermatogenesis as evidenced by microscopic and ultrastructural studies and affection of ERβ receptors and vitamin B12 has a protective action against this harmful effect.

Licochalcone A: An effective and low-toxicity compound against Toxoplasma gondii in vitro and in vivo

Toxoplasma gondii, an obligate intracellular protozoan, is the causative agent of toxoplasmosis, which can cause serious public health problems. The current drugs used to treat toxoplasmosis have many limitations. This study evaluated the anti-T. gondii activity and potential mechanism of Licochalcone A (Lico A) in vitro and in vivo. The safe concentration of Lico A in HFF cells was determined by MTT cell viability assays. The presence of T. gondii was assessed by qPCR and Giemsa staining. Azithromycin and sulfadiazine, commonly used effective treatments, served as drug controls. T. gondii ultrastructural alterations were observed by electron microscopy. The anti-T. gondii activity of Lico A was evaluated using an in vivo mouse infection model. In vitro, Lico A had no negative effect on host cell viability at concentrations below 9 μg/mL; however, it did inhibit T. gondii proliferation in a dose-dependent manner, with a 50% inhibitory concentration (IC₅₀) of 0.848 μg/mL. Electron microscopy analyses indicated substantial structural and ultrastructural changes in tachyzoites after Lico A treatment. Nile Red staining assays demonstrated that Lico A caused lipid accumulation. Lico A treatment significantly increased the survival rate of BALB/c mice infected with T. gondii. Lico A achieved the same therapeutic effect as a commonly used clinical drugs (combination of sulfadiazine, pyrimethamine and folinic acid). In conclusion, Lico A has strong anti-T. gondii activity in vitro and in vivo and might be developed into a new anti-T. gondii drug. Moreover, Lico A may exert these effects by interfering with lipid metabolism in the parasite.

Electron microscopic ultrastructural study on the toxicological effects of AgNPs on the liver, kidney and spleen tissues of albino mice

The present study deals with the intraperitoneal administration of 500, 1000, 3000, and 5000mg/kg of AgNPs in albino mice for 28 days to evaluate the potential toxicological effects of AgNPs on blood biochemical parameters and to investigate the light and electron microscopic histopathological alterations on three major targets organs i.e., liver, kidney and spleen. The AgNPs was well tolerated and no mortality was observed even at the highest dose i.e., 5000mg/kg. Mice treated with 500 and 1000mg/kg AgNPs did not show significant behavioral, biochemical and ultrastructural pathological changes. Mice treated with 1000mg/kg AgNPs produces little ultrastructural alteration in liver, kidney and spleen. However, mice treated with 3000 and 5000mg/kg AgNPs revealed significant changes in biochemical parameters. Electron microscopic ultrastructural investigation of liver and kidney shows that the administration of 3000 and 5000mg/kg AgNPs revealed irregularity in the nuclear membrane, nuclear chromatin condensations, degenerated hepatocytes, swollen and pleomorphic mitochondria with distorted cristae, extensive dilation of rough endoplasmic reticulum, destructed cytoplasm, hypertrophied and fused podocytes and thickened basement membrane in the endothelial cells of the proximal tubules. The spleen sections at 3000 and 5000mg/kg AgNPs revealed megakaryocytes hyperplasia, lobulations, invaginations and folding of nuclei and nuclear membrane. The present research indicates that AgNPs were well tolerated at the lower doses, but significant alterations in liver, kidney and spleen were observed at the higher doses tested. It is, therefore, suggested that further studies are needed for the minimization of the observed side effects, especially at higher doses before AgNPs being applied in pharmaceutical application.

Hemocytes of Rhipicephalus sanguineus (Acari: Ixodidae): Characterization, Population Abundance, and Ultrastructural Changes Following Challenge with Leishmania infantum

Few studies have examined the cellular immune response of ticks, and further research on the characterization of the hemocytes of ticks is required, particularly on those of Rhipicephalus sanguineus (Latreille) because of the medical and veterinary importance of this tick. The aims of this study were to characterize the morphology and the ultrastructure of the different types of hemocytes of adult R. sanguineus and to determine the population abundance and the ultrastructural changes in the hemocytes of ticks infected with Leishmania infantum. The hemocytes were characterized through light and transmission electron microscopy. Within the variability of circulating cells in the hemolymph of adult R. sanguineus, five cell types were identified, which were the prohemocytes, plasmatocytes, granulocytes, spherulocytes, and adipohemocytes. The prohemocytes were the smallest cells found in the hemolymph. The plasmatocytes had polymorphic morphology with vesicles and cytoplasmic projections. The granulocytes had an elliptical shape with the cytoplasm filled with granules of different sizes and electrodensities. The spherulocytes were characterized by several spherules of uniform shapes and sizes that filled the entire cytoplasm, whereas the adipohemocytes had an irregular shape with multiple lipid inclusions that occupied almost the entire cytoplasmic space. The total counts of the hemocyte population increased in the group that was infected with L. infantum. Among the different cell types, the numbers increased and the ultrastructural changes occurred in the granulocytes and the plasmatocytes in the infected group of ticks.

Potential ultrastructural changes in rat epididymal cell types induced by Boswellia papyrifera and Boswellia carterii incense

Boswellia papyrifera and Boswellia carterii, known as Arabian incense, diffuses smoke, contaminating the air, which adversely affects human health. Therefore, this study was designed to ascertain the effect of these plants on histopathological and ultrastructure changes in cauda epididymis of Albino rats. Animals were exposed to 4 g/kg body weight of B. papyrifera and B. carterii daily for 120 days along with suitable controls. Our study indicates a significant reduction in epithelial heights. Cells showed signs of degeneration. The ultrastructural study revealed that the cauda epididymis was affected, including its cell types. Furthermore, a decrease in the size of mitochondria, Golgi complex, and both ERs was observed. In all treated groups, plasma fructose decreased considerably, indicating the sign of reduced energy, vital for motility and other sperm functions. The results of this study suggest that these plants systematically affect cauda epididymal cell types and its lumen through its potential toxicity.