Animal models of kidney iron overload and ferroptosis: a review of the literature.

In recent years, it has been identified that excess iron contributes to the development of various pathologies and their complications. Kidney diseases do not escape the toxic effects of iron, and ferroptosis is identified as a pathophysiological mechanism that could be a therapeutic target to avoid damage or progression of kidney disease. Ferroptosis is cell death associated with iron-dependent oxidative stress. To study the effects of iron overload (IOL) in the kidney, numerous animal models have been developed. The methodological differences between these models should reflect the IOL-generating mechanisms associated with human IOL diseases. A careful choice of animal model should be considered for translational purposes.

Insight into the Burden of Malignant Respiratory Tumors and their Relationship with Smoking Rates and Lead Contamination in Mexico.

We aimed to report the results from the Global Burden of Disease Study 2019 related to respiratory malignant tumors (tracheal, bronchial, and lung) in Mexico. We also evaluated the relationship between the burden of these neoplasms and the proportion of daily smokers and total lead emissions in 2019. A cross-sectional analysis of ecological data was performed. The burden of these tumors was 152,189 disability-adjusted life-years (DALYs), and years of life lost (YLL) contributed to 99% of them. The highest DALYs rates (per 100,000) were observed in the states of Sinaloa, Chihuahua, Baja California Sur, Sonora, and Nayarit. We documented a linear relationship between the DALYs rates and the prevalence of daily smokers (ß = 8.50, 95% CI 1.58-15.38) and the total lead emissions (tons/year: ß = 4.04, 95% CI 0.07-8.01). If later replicated, our study would provide insight into the major relevance of regulating tobacco use and the activities associated with the production of lead dust and other hazardous contaminants.

Capsaicin Decreases Kidney Iron Deposits and Increases Hepcidin Levels in Diabetic Rats with Iron Overload: A Preliminary Study.

Iron overload (IOL) increases the risk of diabetes mellitus (DM). Capsaicin (CAP), an agonist of transient receptor potential vanilloid-1 (TRPV1), reduces the effects of IOL. We evaluated the effects of chronic CAP administration on hepcidin expression, kidney iron deposits, and urinary biomarkers in a male Wistar rat model with IOL and DM (DM-IOL). IOL was induced with oral administration of iron for 12 weeks and DM was induced with streptozotocin. Four groups were studied: Healthy, DM, DM-IOL, and DM-IOL + CAP (1 mg·kg-1·day-1 for 12 weeks). Iron deposits were visualized with Perls tissue staining and a colorimetric assay. Serum hepcidin levels were measured with an enzyme-linked immunosorbent assay. Kidney biomarkers were assayed in 24 h urine samples. In the DM-IOL + CAP group, the total area of iron deposits and the total iron content in kidneys were smaller than those observed in both untreated DM groups. CAP administration significantly increased hepcidin levels in the DM-IOL group. Urinary levels of albumin, cystatin C, and beta-2-microglobulin were similar in all three experimental groups. In conclusion, we showed that in a DM-IOL animal model, CAP reduced renal iron deposits and increased the level of circulating hepcidin.

Independent risk factors of COVID-19 pneumonia in vaccinated Mexican adults.

OBJECTIVES: To evaluate host factors associated with the risk of coronavirus disease 2019 (COVID-19) pneumonia in vaccinated adults. METHODS: A cohort study was conducted in Mexico, and data from 1607 adults with confirmed illness, with a positive history of COVID-19 vaccination, were analyzed. Risk ratios (RR) and 95% confidence intervals (CI) were computed as a measure of the significance of the associations between putative risk factors and the prevalence of COVID-19 pneumonia in vaccinated subjects. RESULTS: The overall risk of pneumonia was 1.98 per 1000 person-days. In the multiple regression analysis, older subjects, those with a history of smoking (current), obesity, and type 2 diabetes mellitus were at increased risk of pneumonia. CONCLUSIONS: Our results suggest that the effectiveness of COVID-19 vaccines may be reduced in a subset of adults who are older aged, smokers, obese, or have type 2 diabetes mellitus.

Effects of dietary iron restriction on kidney mitochondria function and oxidative stress in streptozotocin-diabetic rats.

Diabetes mellitus is characterized by chronic hyperglycemia causing mitochondrial dysfunction and kidney iron overload has been observed during diabetes. We evaluated the effects of an iron-restricted diet (IRD) on mitochondrial function, oxidative stress, and mitochondrial iron levels in the kidneys of Wistar rats with streptozotocin-induced diabetes. IRD ameliorated mitochondrial dysfunction in diabetic rats by restoring mitochondrial respiration and respiratory complex activity, improving oxidative stress and glutathione status in kidney mitochondria. We also observed mitochondrial iron overload. Our data suggest that elevated iron levels were attenuated by IRD, resulting in modulation of oxidative stress and mitochondrial function in the kidney.

Effects of Chronic Administration of Capsaicin on Biomarkers of Kidney Injury in Male Wistar Rats with Experimental Diabetes.

Capsaicin is an agonist of the transient receptor potential vanilloid type 1 (TRPV1) channel, which has been related to the pathophysiology of kidney disease secondary to diabetes. This study aimed to evaluate the chronic effect of capsaicin administration on biomarkers of kidney injury in an experimental rat model of diabetes. Male Wistar rats were assigned to four groups: (1) healthy controls without diabetes (CON), (2) healthy controls plus capsaicin at 1 mg/kg/day (CON + CAPS), (3) experimental diabetes without capsaicin (DM), and (4) experimental diabetes plus capsaicin at 1 mg/kg/day (DM + CAPS). For each group, 24-h urine samples were collected to determine diuresis, albumin, cystatin C, ß2 microglobulin, epidermal growth factor (EGF), alpha (1)-acid glycoprotein, and neutrophil gelatinase-associated lipocalin (NAG-L). Blood samples were drawn to measure fasting glucose. After 8 weeks, the CON + CAPS and DM + CAPS groups showed increased diuresis compared to the CON and DM groups, but the difference was significant only in the DM + CAPS group. The two-way ANOVA only showed a statistically significant effect of CAPS on the urinary EGF levels, as well as a tendency to have a significant effect in the urinary NAG-L levels. The EGF levels decreased in both CAPS-treated groups, but the change was only significant in the CON + CAPS group vs. CON group; and the NAG-L levels were lower in both CAPS-treated groups. These results show that capsaicin had a diuretic effect in healthy and diabetic rats; additionally, it increased the urinary EGF levels and tended to decrease the urinary NAG-L levels.

Disability-Adjusted Life Years for Cancer in 2010⁻2014: A Regional Approach in Mexico.

The disability-adjusted life years (DALYs) were used to estimate the regional (state of Colima, Mexico) cancer burden in 2010⁻2014. The years of life lost (YLL) were estimated with mortality data and years lived with disability (YLD) using incidence data. The DALYs were calculated as the arithmetic addition of YLL and YLD. Sex and cancer site-specific estimations were made and DALY rates were used to identify the leading causes of disease burden. Data from 2532 deaths were analyzed and, for all malignant tumors combined, 18,712.9 DALYs and 20,243.3 DALYs were estimated in males and females respectively. The overall contribution of YLL in DALY estimates was higher among females (93.7% vs. 87.4%). Age-standardized DALY rates (and 95% confidence intervals, CI) per 100,000 inhabitants were used to rank the leading causes of disease burden and, among males, malignant tumors from the prostate, lower respiratory tract, and colon and rectum accounted the highest rates (45.7, 95% CI 32.7⁻59.3; 37.6, 95% CI 25.7⁻49.9; and 25.9, 95% CI 16.0⁻36.1 DALYs). Breast, cervix uteri, and lower respiratory tract cancer showed the highest burden in females (66.0, 95% CI 50.3⁻82.4; 44.4, 95% CI 31.5⁻57.7; and 20.9, 95% CI 12.0⁻30.0 DALYs). The present study provides an indication of the burden of cancer at the regional level, underscoring the need to expand cancer prevention, screening, and awareness programs, as well as to improve early diagnosis and medical treatment.

The Effects of Dietary Iron and Capsaicin on Hemoglobin, Blood Glucose, Insulin Tolerance, Cholesterol, and Triglycerides, in Healthy and Diabetic Wistar Rats.

OBJECTIVE: Our aim was to assess the effects of dietary iron, and the compound capsaicin, on hemoglobin as well as metabolic indicators including blood glucose, cholesterol, triglycerides, insulin, and glucose tolerance. MATERIALS AND METHODS: Our animal model was the Wistar rat, fed a chow diet, with or without experimentally induced diabetes. Diabetic males were fed control, low, or high-iron diets, the latter, with or without capsaicin. Healthy rats were fed identical diets, but without the capsaicin supplement. We then measured the parameters listed above, using the Student t-test and ANOVA, to compare groups. RESULTS: Healthy rats fed a low-iron diet exhibited significantly reduced total cholesterol and triglyceride levels, compared with rats fed a control diet. Significantly reduced blood lipid was also provoked by low dietary iron in diabetic rats, compared with those fed a control diet. Insulin, and glucose tolerance was only improved in healthy rats fed the low-iron diet. Significant increases in total cholesterol were found in diabetic rats fed a high-iron diet, compared with healthy rats fed the same diet, although no statistical differences were found for triglycerides. Hemoglobin levels, which were not statistically different in diabetic versus healthy rats fed the high-iron diet, fell when capsaicin was added. Capsaicin also provoked a fall in the level of cholesterol and triglycerides in diabetic animals, versus diabetics fed with the high iron diet alone. In conclusion, low levels of dietary iron reduced levels of serum triglycerides, hemoglobin, and cholesterol, and significantly improved insulin, and glucose tolerance in healthy rats. In contrast, a high-iron diet increased cholesterol significantly, with no significant changes to triglyceride concentrations. The addition of capsaicin to the high-iron diet (for diabetic rats) further reduced levels of hemoglobin, cholesterol, and triglycerides. These results suggest that capsaicin, may be suitable for the treatment of elevated hemoglobin, in patients.

Factor de riesgo para cesárea: un enfoque epidemiológico / Risk factors for cesarea: an epidemiological view

El incremento en la frecuencia de cesáreas notado a partir de la década de los setenta no disminuyó como se esperaba la morbilidad y mortalidad perinatales. Las principales indicaciones de cesárea son distocias, cesárea previa y sufrimiento fetal. En 1998 la frecuencia de cesáreas en nuestro hospital fue de 35 por ciento de los embarazos atendidos. Mediante un estudio de casos y controles se determinaron los factores de riesgo para cesárea en nuestra unidad hospitalaria. Se seleccionaron 165 casos (cesáreas) y 328 controles (partos). Se determinó razón de momios (OR) y fracción atribuible (FA) de los factores de riesgo. Se analizaron los datos mediante X2. Las indicaciones más importantes de cesárea fueron: distocias (39 por ciento, n= 64); cesárea previa (23 por ciento, n=41) y sufrimiento fetal (11 por ciento, n=21). No hubo diferencias significativas en edad, estatura y tiempo de rotura de membranas entre ambos grupos. El antecedente de cesárea confirió mayor riesgo para una nueva intervención quirúgica (OR= 12.7, p= < 0.0001, FA= 92 por ciento). Ser nulípara (OR= 6.6, p < 0.001, FA= 85 por ciento), secundigesta (OR= 1.8, p= 0.002, FA= 19 por ciento) o con antecedente de abortos (OR= 1.8, p= 0.04, FA= 45 por ciento) fueron factores mayormente asociados a cesárea. Concluimos que deben replantearse las indicaciones precisas de esta intervención quirúrgica ,sobre todo en casos de nuliparidad o de cesárea previa para disminuir su elevada frecuencia.