Potential Satellite Cell-Linked Biomarkers in Aging Skeletal Muscle Tissue: Proteomics and Proteogenomics to Monitor Sarcopenia.

Sarcopenia (Sp) is the loss of skeletal muscle mass associated with aging which causes an involution of muscle function and strength. Satellite cells (Sc) are myogenic stem cells, which are activated by injury or stress, and repair muscle tissue. With advancing age, there is a decrease in the efficiency of the regenerative response of Sc. Diagnosis occurs with the Sp established by direct assessments of muscle. However, the detection of biomarkers in real-time biofluids by liquid biopsy could represent a step-change in the understanding of the molecular biology and heterogeneity of Sp. A total of 13 potential proteogenomic biomarkers of Sp by their physiological and biological interaction with Sc have been previously described in the literature. Increases in the expression of GDF11, PGC-1α, Sirt1, Pax7, Pax3, Myf5, MyoD, CD34, MyoG, and activation of Notch signaling stimulate Sc activity and proliferation, which could modulate and delay Sp progression. On the contrary, intensified expression of GDF8, p16INK4a, Mrf4, and activation of the Wnt pathway would contribute to early Sp development by directly inducing reduced and/or altered Sc function, which would attenuate the restorative capacity of skeletal muscle. Additionally, tissue biopsy remains an important diagnostic tool. Proteomic profiling of aged muscle tissues has shown shifts toward protein isoforms characteristic of a fast-to-slow transition process and an elevated number of oxidized proteins. In addition, a strong association between age and plasma values of growth differentiation factor 15 (GDF-15) has been described and serpin family A member 3 (serpin A3n) was more secreted by atrophied muscle cells. The identification of these new biomarkers holds the potential to change personalized medicine because it could predict in real time the course of Sp by monitoring its evolution and assessing responses to potential therapeutic strategies.

Effectiveness of Comirnaty® Vaccine and Correlates of Immunogenicity and Adverse Reactions: A Single-Center Prospective Case Series Study.

The literature suggests that real-world data on the effectiveness and safety of the BNT162b2 vaccine depend on the characteristics of the vaccinated volunteers. The purpose of this study was to evaluate antibody responses and kinetics, established association with sociodemographic and clinical characteristics, and adverse reactions after complete vaccination with the BNT162b2 vaccine. A single-center prospective case series study was conducted with 112 eligible volunteers who were institutionalized elderly and health care workers with had a negative anti-SARS-CoV-2 IgG test prior to receiving the first dose of vaccine. At least one serological antibody test after each dose of vaccine was performed. Volunteers with a positive SARS-CoV-2 PCR test before vaccination were excluded. A chemiluminescent immunoassay anti-S1 antibody assay performed a serological evaluation. Both vaccine doses elicited positive IgG antibodies 3799.0 ± 2503.0 AU/mL and 8212.0 ± 4731.0 AU/mL after 20 days of the first and second doses of BNT162b2, respectively. Comirnaty® vaccine induced an immune response with antibody production against SARS-CoV-2 in 100% of participants, regardless of age (Spearman rho = −0.10, p-value = 0.312), body mass index (Spearman rho = 0.05, p-value = 0.640), blood group first dose (p-value for Kruskal−Wallis test = 0.093) and second dose (p-value for Kruskal−Wallis test = 0. 268), number of drugs (Spearman rho = −0.07, p-value = 0.490), and number of chronic diseases first dose (p-value for Kruskal−Wallis test = 0.632) and second dose (p-value for Kruskal−Wallis test = 0.510). IgG antibodies to SARS-CoV-2 were intensely elevated after the second administration of the BNT162b2 vaccine. The higher the titer of anti-peptide IgG antibodies generated after the first dose of vaccine, the higher the titer generated by the second dose of vaccine (Spearman rho = 0.86, p-value < 0.001) and the total antibody titer (Spearman rho = 0.93, p-value < 0.001). Furthermore, no serious adverse effects were reported among participants, although mild to moderate adverse effects (local or systemic) were reported after both doses of the BNT162b2 vaccine, being more frequent after the first dose of the vaccine. No participants showed a positive PCR. The BNT162b2 vaccine induces a robust and rapid antibody response regardless of participant characteristics. The second dose might be especially important because of the increased immunogenicity it produces and the possible temporal distancing of the interval between doses. In general, the vaccines were well tolerated.

Influencia de la densidad de energía de ondas de choque focalizadas en el tratamiento de la fascitis plantar / Influence of energy density on the effectiveness of the treatment of plantar fasciitis with focused extracorporeal shock waves

Resumen La fascitis plantar (FP) es una patología frecuente e invalidante que puede tratarse con ondas de choque focalizadas. El objetivo principal del estudio fue valorar la eficacia del tratamiento con ondas de choque focalizadas en la FP según la densidad de energía utilizada. Se incluyeron 82 pacientes con diagnóstico clínico de FP que fueron asignados mediante muestreo aleatorio simple a dos grupos de tratamiento: densidad de energía media- alta (0,59mJ/mm2) y densidad de energía media-baja (0,27mJ/mm2). Se evaluaron el dolor y la funcionalidad, mediante las escalas EVA (Escala Visual Analógica) y AOFAS (American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale) respectivamente, al inicio del estudio (consulta base), y al primer, tercer y sexto mes tras el tratamiento. Por último, se evaluó el grado de satisfacción de los pacientes mediante la escala de Roles y Maudsley. Se compararon los resultados de las escalas en las revisiones posteriores al tratamiento, obteniéndose significación estadística para las variables principales del estudio (dolor y funcionalidad) en cada grupo de intervención. Aunque los niveles de dolor y la funcionalidad mejoraron en ambos grupos de estudio, se obtuvo una respuesta analgésica y funcional mayor y más precoz en el grupo tratado con densidad de energía media-alta.

Abstract Plantar fasciitis (FP) is a frequent and disabling condition that can be treated with focused extracorporeal shock waves. The main objective of this study was to assess the effectiveness of focused extracorporeal shockwave treatment in FP according to the energy density used. Eighty-two patients with a clinical diagnosis of FP were included and assigned, by simple random sampling, to two treatment groups: medium-high energy density (0.59mJ/mm2) and low-medium energy density (0.27mJ/mm2). Pain and functionality were assessed using the VAS (Visual Analogical Scale) and AOFAS (American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale) scales, respectively, at the start of the study (baseline consultation), and at the first, third and sixth month post-treatment. Finally, the degree of patient satisfaction was evaluated using the Roles and Maudsley score. The results of the scales in the post-treatment reviews were compared, and statistical significance was obtained for the main study variables (pain and functionality) in each intervention group. Although pain levels and functionality improved in both study groups after treatment, a greater and earlier analgesic and functional response was obtained for the medium-high energy density group.

Identification, Mechanism, and Treatment of Skin Lesions in COVID-19: A Review.

Coronavirus disease 2019 (COVID-19) is a multisystem disease caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), that primarily causes respiratory symptoms. However, an increasing number of cutaneous manifestations associated with this disease have been reported. The aim of this study is to analyze the scientific literature on cutaneous manifestations associated with SARS-CoV-2 by means of a narrative literature review until June 2021. The search was conducted in the following electronic databases: Medline (PubMed), SciELO, and Cochrane Library Plus. The most common cutaneous manifestations in patients with COVID-19 are vesicular eruptions, petechial/purpuric rashes, acral lesions, liveoid lesions, urticarial rash, and maculopapular-erythematous rash. These manifestations may be the first presenting symptoms of SARS-CoV-2 infection, as is the case with acral lesions, vesicular eruptions, and urticaria. In relation to severity, the presence of liveoid lesions may be associated with a more severe course of the disease. Treatment used for dermatological lesions includes therapy with anticoagulants, corticosteroids, and antihistamines. Knowledge of the dermatologic manifestations associated with SARS-CoV-2 contributes to the diagnosis of COVID-19 in patients with skin lesions associated with respiratory symptoms or in asymptomatic patients. In addition, understanding the dermatologic lesions associated with COVID-19 could be useful to establish a personalized care plan.

Pathological and Therapeutic Approach to Endotoxin-Secreting Bacteria Involved in Periodontal Disease.

It is widely recognized that periodontal disease is an inflammatory entity of infectious origin, in which the immune activation of the host leads to the destruction of the supporting tissues of the tooth. Periodontal pathogenic bacteria like Porphyromonas gingivalis, that belongs to the complex net of oral microflora, exhibits a toxicogenic potential by releasing endotoxins, which are the lipopolysaccharide component (LPS) available in the outer cell wall of Gram-negative bacteria. Endotoxins are released into the tissues causing damage after the cell is lysed. There are three well-defined regions in the LPS: one of them, the lipid A, has a lipidic nature, and the other two, the Core and the O-antigen, have a glycosidic nature, all of them with independent and synergistic functions. Lipid A is the "bioactive center" of LPS, responsible for its toxicity, and shows great variability along bacteria. In general, endotoxins have specific receptors at the cells, causing a wide immunoinflammatory response by inducing the release of pro-inflammatory cytokines and the production of matrix metalloproteinases. This response is not coordinated, favoring the dissemination of LPS through blood vessels, as well as binding mainly to Toll-like receptor 4 (TLR4) expressed in the host cells, leading to the destruction of the tissues and the detrimental effect in some systemic pathologies. Lipid A can also act as a TLRs antagonist eliciting immune deregulation. Although bacterial endotoxins have been extensively studied clinically and in a laboratory, their effects on the oral cavity and particularly on periodontium deserve special attention since they affect the connective tissue that supports the tooth, and can be linked to advanced medical conditions. This review addresses the distribution of endotoxins associated with periodontal pathogenic bacteria and its relationship with systemic diseases, as well as the effect of some therapeutic alternatives.

Unexpected Toxicity of Green Tea Polyphenols in Combination with the Sambucus RIL Ebulin.

The safety of concentrated food complements intake is a major health concern. It has been well established that green tea polyphenols (GTPs) consumption promotes healthy effects. However, the ingestion of large amounts of GTPs is a matter of controversy due to reported adverse effects. We underwent a preliminary exploration of the effects of the oral administration of a standardized concentrated GTPs preparation on mice which suffered from reversible intestinal derangement promoted by sublethal amounts of the antiribosomal lectin ebulin f from dwarf elder (Sambucus ebulus L.). Neither independent oral administration of 30 mg/kg body weight Polyphenon 60 nor intraperitoneal administration of 2.5 mg/kg body weight ebulin f triggered lethal toxicity. In contrast, the simultaneous administration of these same doses of both Polyphenon 60 and ebulin f triggered an important and unexpected synergistic toxic action featured by the biphasic reduction of weight, which continued after eight days, reaching a reduction of 40%. Lethality appeared 2 days after the onset of the combined treatment and reached more than 50% after 10 days.

Three-sectioning method: A procedure for studying hard tissues and large pieces under light and electron microscopy.

The histological study of hard pieces such as tendons and calcified lesions and tissues is a field that has been gaining increased attention owing to the rapid development of implantable prostheses, among other factors. In these studies, serial sectioning is utilized to detect areas of interest throughout the entire piece, as it enables the application of the appropriate light and electron microscopy techniques in these areas. We propose the "three-sectioning method" that subjects the pieces to three consecutive cycles of embedding and sectioning to localize and study the areas of interest, as an efficient technique for these histological studies. The pieces were first embedded in epoxy resin and then cut into thick sections (approximately 300 µm) for the first cycle. Next, areas of interest selected on these thick sections were re-embedded in epoxy resin to be sectioned again (second sectioning) to obtain a series of semithin sections (1-3 µm). These semithin sections are usually studied using the most relevant techniques for light microscopy. Smaller areas of interest are selected to be cut into ultrathin sections (60-90 nm) for transmission electron microscopy. If necessary, the selected areas of the semithin sections can be embedded again, and then cut into new ultrathin sections. The different kinds of sections we have described here may also be studied using scanning electron microscopy. This systematic method facilitates correlative microscopy from lower to higher magnifications along with the usage of a broad variety of histological techniques including electron microscopy.

Human Health Effects of Lactose Consumption as a Food and Drug Ingredient.

Lactose is a reducing sugar consisting of galactose and glucose, linked by a ß (1→4) glycosidic bond, considered as an antioxidant due to its α-hydroxycarbonyl group. Lactose is widely ingested through the milk and other unfermented dairy products and is considered to be one of the primary foods. On the other hand, lactose is also considered as one of the most widely used excipients for the development of pharmaceutical formulations. In this sense, lactose has been related to numerous drug-excipient or drug-food pharmacokinetic interactions. Intolerance, maldigestion and malabsorption of carbohydrates are common disorders in clinical practice, with lactose-intolerance being the most frequently diagnosed, afflicting 10% of the world's population. Four clinical subtypes of lactose intolerance may be distinguished, namely lactase deficiency in premature infants, congenital lactase deficiency, adult-type hypolactasia and secondary lactase intolerance. An overview of the main uses of lactose in human nutrition and in the pharmaceutical industry and the problems derived from this circumstance are described in this review.

Endotoxins from a Pharmacopoeial Point of View.

A pyrogen is a substance that causes fever after intravenous administration or inhalation. Gram negative endotoxins are the most important pyrogens to pharmaceutical laboratories. In the International, United States, Japanese and European Pharmacopoeias, there are two official methods to evaluate pyrogenicitythat is, the bacterial endotoxin test, and the pyrogen test. The main objective of this review is to compare the monographs of each test among the different Pharmacopeias, to detect similarities and differences. The former can be considered fully harmonized, and only non-significant differences were detected. The latter, which is the only available assay for some products and formulations to demonstrate apyrogenicity, shows large differences, which should be considered.

The ligamentum teres femoris in orangutans.

OBJECTIVES: It is widely viewed that orangutans lack a ligamentum teres femoris (LTF) inserting on the femoral head because orangutans lack a distinct fovea capitis. Orangutans employ acrobatic quadrumanous clambering that requires a high level of hip joint mobility, and the absence of an LTF is believed to be an adaptation to increase hip mobility. However, there are conflicting reports in the literature about whether there may be a different LTF configuration in orangutans, perhaps with a ligament inserting on the femoral neck instead. Here we perform a dissection-based study of orangutan hip joints, assess the soft tissue and hard tissue correlates of the orangutan LTF, and histologically examination the LTF to evaluate whether it is homologous to that found in other hominoids. MATERIALS AND METHODS: The hip joints from six orangutans were dissected. In the two orangutans with an LTF passing to the femoral head, the LTF was assessed histologically. Skeletonized femora (n=56) in osteological repositories were examined for evidence of a foveal pit. RESULTS: We observed an LTF in two of the three infant orangutans but not in the sub-adult or adult specimens. Histological examination of the infant LTF shows a distinct artery coursing through the LTF to the head of the femur. One percent of orangutan femora present with a foveal scar, but no pit, on the femoral head. DISCUSSION: Despite being absent in adults, the LTF is present in at least some orangutans during infancy. We suggest that the LTF maintains a role in blood supply to the femoral head early in life. Because the LTF can limit hip mobility, this may explain why the LTF may be lost as an orangutan ages and gains locomotor independence. These findings enhance our understanding of orangutan hip morphology and underscore the need for future soft tissue investigations.

In vivo toxicity of the ribosome-inactivating lectin ebulin f in elderly mice.

Ebulin f is a ribosome-inactivating protein (RIP) present in green fruits of the dwarf elder (Sambucus ebulus L). Since dwarf elder fruits are used for food and as a medicine, we assessed the study of toxicological effects and safety of ebulin f in elderly mice, comparing these results with those reported in young animals and with other RIPs. Female Swiss mice aged 6 and 12 months of age were intraperitoneally injected with a single dose from 1.4 to 4.5 mg/kg ebulin f. Heart, stomach, intestines, lung, kidney, liver, spleen, pancreas, adrenal gland, uterus, ovary and brain were studied. Histology analysis was carried out by staining with hematoxylin and eosin and Masson's trichrome observed with a light microscope, or apoptosis detection by TUNEL method observed with a confocal laser microscope. Treated animals injected with the lower dose could recover their weights, but after 14 days half of them died. The higher dose caused a progressive loss of body weight leading to death. In the animals of the experimental groups it was found atrophy of Lieberkühn's crypts, pneumonia, nephronal degeneration, myocardial atrophy, centrolobular hepatic necrosis, splenic white pulp necrosis foci and increased rate of apoptosis in the intestines and liver, in which apoptoses were mainly located in the vicinity of the lobular central vein. We conclude that ebulin f affects vital organs in elderly mice.

Lectin Digestibility and Stability of Elderberry Antioxidants to Heat Treatment In Vitro.

Elderberry contains healthy low molecular weight nutraceuticals and lectins which are sequence-related to the elderberry allergen Sam n1. Some of these lectins are type II ribosome-inactivating proteins. The sensitivity of native lectins present in elderberry fruits and bark to the proteolysis triggered by in vitro simulated gastric and duodenal fluids has been investigated. It was found that these lectins are refractory to proteolysis. Nonetheless, incubation for 5-10 min in a boiling water bath completely sensitized them to the hydrolytic enzymes in vitro. Under these conditions neither total Folin-Ciocalteau's reagent reactive compounds, total anthocyanins and the mixture of cyanidin-3-glucoside plus cyanidin-3-sambubioside, nor antioxidant and free-radical scavenging activities were affected by more than 10% for incubations of up to 20 min. Therefore, short-time heat treatment reduces potential allergy-related risks deriving from elderberry consumption without seriously affecting its properties as an antioxidant and free-radical scavenging food.

The "Big-Bang" for modern glial biology: Translation and comments on Pío del Río-Hortega 1919 series of papers on microglia.

The word "glia" was coined in the mid-19th century and defined as "the nerve glue". For decades, it was assumed to be a uniform matrix, until cell theorists raised the "neuron doctrine" which stipulated that nervous tissue was composed of individual cells. The term "astrocytes" was introduced in the late 19th century as a synonym for glial cells, but it was Santiago Ramón y Cajal who defined a "third element" distinct from glial cells (astrocytes) and neurons. It was not until 1919 when Pío del Río-Hortega, an alumnus of the Cajal School, introduced the modern terms we use today, and thoroughly described both "oligodendrocytes" and "microglia" to clearly distinguish them from astrocytes. In a series of four papers published that year in Spanish, Río-Hortega described the distribution and morphological phenotype of microglia. He also noted that these cells were the origin of the rod cells described earlier in pathologic tissue, and recognized that resting microglia transformed into an ameboid phenotype in different types of brain diseases and pathologies. He also noted the mesodermal origin of these cells and recognized their phagocytic capacity. We here provide the first English translation of these landmark series of papers, which paved the way for modern glial research. To heighten the value and accessibility of these classic papers and their original figures, an introduction to this critical period of neuroscience is provided, along with unpublished photographs. By adding comments to the translated text, we provide sufficient context so that contemporary scientists may fully appreciate it. GLIA 2016;64:1801-1840.

Toxicity of the anti-ribosomal Lectin Ebulin f in lungs and intestines in elderly mice.

All parts of dwarf elder (Sambucus ebulus L.) studied so far contain a ribosome-inactivating protein with lectin activity (ribosome-inactivating lectin; RIL), known as ebulin. Green fruits contain ebulin f, the toxicity of which has been studied in six-week-old mice, where it was found that the intestines were primary targets for it when administered intraperitoneally (i.p.). We performed experiments to assess whether ebulin f administration to six- and 12-month-old mice would trigger higher toxicity than that displayed in six-week-old mice. In the present report, we present evidence indicating that the toxicological effects of ebulin f after its i.p. administration to elderly mice are exerted on the lungs and intestines by an increased rate of apoptosis. We hypothesize that the ebulin f apoptosis-promoting action together with the age-dependent high rate of apoptosis result in an increase in the lectin's toxicity, leading to a higher lethality level.

Elderberries: a source of ribosome-inactivating proteins with lectin activity.

Sambucus (Adoxaceae) species have been used for both food and medicine purposes. Among these, Sambucus nigra L. (black elder), Sambucus ebulus L. (dwarf elder), and Sambucus sieboldiana L. are the most relevant species studied. Their use has been somewhat restricted due to the presence of bioactive proteins or/and low molecular weight compounds whose ingestion could trigger deleterious effects. Over the last few years, the chemical and pharmacological characteristics of Sambucus species have been investigated. Among the proteins present in Sambucus species both type 1, and type 2 ribosome-inactivating proteins (RIPs), and hololectins have been reported. The biological role played by these proteins remains unknown, although they are conjectured to be involved in defending plants against insect predators and viruses. These proteins might have an important impact on the nutritional characteristics and food safety of elderberries. Type 2 RIPs are able to interact with gut cells of insects and mammals triggering a number of specific and mostly unknown cell signals in the gut mucosa that could significantly affect animal physiology. In this paper, we describe all known RIPs that have been isolated to date from Sambucus species, and comment on their antiviral and entomotoxic effects, as well as their potential uses.

Ebulin from dwarf elder (Sambucus ebulus L.): a mini-review.

Sambucus ebulus L. (dwarf elder) is a medicinal plant, the usefulness of which also as food is restricted due to its toxicity. In the last few years, both the chemistry and pharmacology of Sambucus ebulus L. have been investigated. Among the structural and functional proteins present in the plant, sugar-binding proteins (lectins) with or without anti-ribosomal activity and single chain ribosome-inactivating proteins (RIPs) have been isolated. RIPs are enzymes (E.C. 3.2.2.22) that display N-glycosidase activity on the 28S rRNA subunit, leading to the inhibition of protein synthesis by arresting the step of polypeptide chain elongation. The biological role of all these proteins is as yet unknown. The evidence suggests that they could be involved in the defense of the plant against predators and viruses or/and a nitrogen store, with an impact on the nutritional characteristics and food safety. In this mini-review we describe all the isoforms of ebulin that have to date been isolated from dwarf elder, as well as their functional characteristics and potential uses, whilst highlighting concern regarding ebulin toxicity.

Triple-layered mixed co-culture model of RPE cells with neuroretina for evaluating the neuroprotective effects of adipose-MSCs.

Mesenchymal stem cell (MSC) therapy is promising for neuroprotection but there is no report of an appropriate in vitro model mimicking the situation of the in vivo retina that is able to test the effect of MSCs in suspension or encapsulated with/without a drug combination. This study aims to establish a viable mixed co-culture model having three layers: neuroretina explants (NRs), retinal pigment epithelium (RPE) cells and adipose tissue-derived MSCs (AT-MSCs) for evaluating adipose-MSC effects. AT-MSCs were grown on the lower surface of a transwell membrane and RPE cells were grown on the bottom of a culture plate as monocultures. A transwell membrane was inserted into a culture plate well. NR was placed as an organotypic culture on the upper surface of the transwell membrane. Thus, a triple-layered co-culture setup was constructed. In double-layered setups, NR were co-cultured with AT-MSCs or RPE cells. Optimum medium, experiment execution period and transwell membrane permeability (TMP) were determined. MSC effects on RPE cell proliferation and NR reactive gliosis were evaluated. Limitations were discussed. Our study shows that neurobasal A with DMEM (1:1) mixed medium was suitable for viability of all three layers. AT-MSC growth decreased TMP significantly, 30-60 % in 3- to 6-day periods. Spontaneous NR reactive gliosis limits the experiment execution period to 6 days. AT-MSCs maintained their undifferentiated nature and showed no or limited neuroprotective effects. In this study, we successfully assembled viable double- and triple-layered co-culture setups for AT-MSCs, RPE and NR, optimised conditions for their survival and explored setup Limitations.

Paneth cells are also target of the ribotoxic lectin nigrin b.

Ribosome-inactivating lectins (RILs) are A-B type toxins like ricin whose molecular target is the large rRNA of eukaryotic ribosome. Administration of lethal doses of the RIL nigrin b isolated from elderberry (Sambucus nigra L.) bark triggers specific intestinal derangement. The aim of the present research was to explore the early effects of a lethal dose of nigrin b (16 mg/kg body weight) on the small intestine using light and electron microscopy to ascertain intestinal epithelium changes. 6 h after nigrin administration, the small intestine crypts began to show signs of damage with cells appearing at different stages of apoptosis. 16 h after injection crypts appeared more impaired, including the derangement of Paneth cells. The novelty of our results is that the Paneth cells in the small intestine in addition to stem cells are the early cellular targets for nigrin b.

The discovery of oligodendroglia cells by Rio-Hortega: his original articles. 1921.

Comment on: del Río-Hortega P. Glia with very few processes (oligodendroglia). Clin Neuropathol. 2012; 31: 440-459, originally published in Archivos de Neurobiología. 1921; 2: 16-43 and del Río-Hortega P. Are the glia with very few processes homologous with Schwann cells? Clin Neuropathol. 2012; 31: 460-462, originally published in Bol de la Soc Esp de Biol. 1922; X: 25-28.

Histopathological changes in gerbil liver and kidney after aluminum subchronic intoxication.

Young gerbil livers and kidneys were analyzed by means of light and electron microscope to assess the histopathological changes caused by prolonged systemic aluminum (Al) administration. The experimental group was injected with AlCl3 i.p. for 5 weeks, while litter mates received PBS as sham-injected controls or served as untouched controls. Mortality occurred in 33% of experimental and 12.5% of sham-injected groups. The animals were perfused intracardially with 1% glutaraldehyde plus 1% paraformaldehyde and samples of liver and kidneys were processed for aluminum and iron histochemistry and conventional light- and transmission electron microscopy. White deposits composed of cellular debris appeared on the surface of liver and kidneys and in the mesentery as a consequence of Al treatment. Adherences of Glisson capsule to the diaphragm, as well as scattered small foci of hepatocyte necrosis with non-caseificant microgranulomas and mild portal inflammation, developed in the experimental group. Sham-injected animals also exhibited these granulomas but to a lesser degree. Al deposits were found in experimental animal granulomas and inside macrophages cytoplasm scattered throughout the liver. Iron deposition appeared in pericentral hepatocytes of experimental animals, in granulomas and in portal spaces of the three groups of animals. Ultrastructurally, hepatocytes of experimental animals showed mitochondria hyalinization, disintegration of endoplasmic reticulum and clustering of ribosomes. Phagolysosomes appeared larger and occurred more frequently in both hepatocytes and Kupffer cells of experimental animals. In 2 out of the 6 experimental animals studied, tubular atrophy was present in the renal cortical region, the kidneys of the remaining animals appearing normal. Al and iron were found very occasionally in the kidney parenchyma of experimental animals, while isolated mesangial cells showed iron deposits in a few glomeruli of both experimental and the two groups of control animals.