Effects of glyphosate herbicide ingestion on kidney function in rats on a balanced diet / Efeitos da ingestão do herbicida glifosato na função renal de ratos em uma dieta balanceada

Abstract Introduction: Glyphosate is the most widely used herbicide worldwide and in Brazil. There is currently increasing concern about the effects of glyphosate on human health. The Brazilian Institute for Consumer Protection showed data on the presence of glyphosate in some of Brazil's most consumed ultra-processed products. Currently, regulations on the upper limit for these residues in ultra-processed foods have yet to be established by the National Health Surveillance, and ultra-processed food consumption is independently associated with an increased risk of incident chronic kidney disease. Methods: Since an unbalanced diet can interfere with kidney function, this study aims to investigate the effect of daily intake of 5 mg/kg bw glyphosate in conjunction with a balanced diet and the possible impact on renal function in rats. Kidney function, kidney weight, markers of renal injury, and oxidative stress were evaluated. Results: There was a decrease in kidney weight. The main histopathological alterations in renal tissues were vacuolation in the initial stage and upregulation of the kidney injury marker KIM-1. Renal injury is associated with increased production of reactive oxygen species in mitochondria. Conclusion: This study showed changes in the kidney of rats exposed to a balanced diet with glyphosate, suggesting a potential risk to human kidney. Presumably, ultra-processed food that contain glyphosate can potentiate this risk. The relevance of these results lies in drawing attention to the need to regulate glyphosate concentration in ultra-processed foods in the future.

RESUMO Introdução: O glifosato é o herbicida mais utilizado no mundo e no Brasil. Atualmente, há uma preocupação crescente com os efeitos do glifosato na saúde humana. O Instituto Brasileiro de Defesa do Consumidor apresentou dados sobre a presença de glifosato em alguns dos produtos ultraprocessados mais consumidos no Brasil. Atualmente, as regulamentações sobre o limite máximo desses resíduos em alimentos ultraprocessados ainda não foram estabelecidas pela Vigilância Sanitária Nacional, e o consumo de alimentos ultraprocessados está indepen­dentemente associado a um risco maior de doença renal crônica incidente. Métodos: Como uma dieta desbalanceada pode interferir na função renal, este estudo tem como objetivo investigar o efeito da ingestão diária de 5 mg/kg pc de glifosato em conjunto com uma dieta equilibrada e o possível impacto na função renal em ratos. Foram avaliados função renal, peso dos rins, marcadores de lesão renal e estresse oxidativo. Resultados: Houve redução no peso dos rins. As principais alterações histopatológicas nos tecidos renais foram vacuolização no estágio inicial e regulação positiva do marcador de lesão renal KIM-1. A lesão renal está associada à produção aumentada de espécies reativas de oxigênio nas mitocôndrias. Conclusão: Esse estudo mostrou alterações nos rins de ratos expostos a uma dieta balanceada com glifosato, sugerindo um risco potencial ao rim humano. Presumivelmente, alimentos ultraprocessados que contenham glifosato podem potencializar esse risco. A relevância desses resultados está no fato de chamar a atenção para a necessidade de regulamentar a concentração de glifosato em alimentos ultraprocessados no futuro.

Effects of glyphosate herbicide ingestion on kidney function in rats on a balanced diet.

INTRODUCTION: Glyphosate is the most widely used herbicide worldwide and in Brazil. There is currently increasing concern about the effects of glyphosate on human health. The Brazilian Institute for Consumer Protection showed data on the presence of glyphosate in some of Brazil's most consumed ultra-processed products. Currently, regulations on the upper limit for these residues in ultra-processed foods have yet to be established by the National Health Surveillance, and ultra-processed food consumption is independently associated with an increased risk of incident chronic kidney disease. METHODS: Since an unbalanced diet can interfere with kidney function, this study aims to investigate the effect of daily intake of 5 mg/kg bw glyphosate in conjunction with a balanced diet and the possible impact on renal function in rats. Kidney function, kidney weight, markers of renal injury, and oxidative stress were evaluated. RESULTS: There was a decrease in kidney weight. The main histopathological alterations in renal tissues were vacuolation in the initial stage and upregulation of the kidney injury marker KIM-1. Renal injury is associated with increased production of reactive oxygen species in mitochondria. CONCLUSION: This study showed changes in the kidney of rats exposed to a balanced diet with glyphosate, suggesting a potential risk to human kidney. Presumably, ultra-processed food that contain glyphosate can potentiate this risk. The relevance of these results lies in drawing attention to the need to regulate glyphosate concentration in ultra-processed foods in the future.

The Nephroprotective Effects of the Allogeneic Transplantation with Mesenchymal Stromal Cells Were Potentiated by ω3 Stimulating Up-Regulation of the PPAR-γ.

Mesenchymal stromal cells (MSCs) obtained from bone marrow are a promising tool for regenerative medicine, including kidney diseases. A step forward in MSCs studies is cellular conditioning through specific minerals and vitamins. The Omega-3 fatty acids (ω3) are essential in regulating MSCs self-renewal, cell cycle, and survival. The ω3 could act as a ligand for peroxisome proliferator-activated receptor gamma (PPAR-γ). This study aimed to demonstrate that ω3 supplementation in rats could lead to the up-regulation of PPAR-γ in the MSCs. The next step was to compare the effects of these MSCs through allogeneic transplantation in rats subjected to unilateral ureteral obstruction (UUO). Independent of ω3 supplementation in the diet of the rats, the MSCs in vitro conserved differentiation capability and phenotypic characteristics. Nevertheless, MSCs obtained from the rats supplemented with ω3 stimulated an increase in the expression of PPAR-γ. After allogeneic transplantation in rats subjected to UUO, the ω3 supplementation in the rats enhanced some nephroprotective effects of the MSCs through a higher expression of antioxidant enzyme (SOD-1), anti-inflammatory marker (IL-10), and lower expression of the inflammatory marker (IL-6), and proteinuria.

Comparison of olive leaf, olive oil, palm oil, and omega-3 oil in acute kidney injury induced by sepsis in rats.

BACKGROUND: Hypotension, increased production of reactive oxygen species, and inflammation are all observed in experimental models of sepsis induced by lipopolysaccharide (LPS). PURPOSE: The aim of this study was to evaluate the effects of an ethanolic extract of Brazilian olive leaf (Ex), Brazilian olive oil (Olv), Ex + Olv (ExOlv), and palm oil (Pal) in comparison to the effects of omega-3 fish oil (Omg) in a rat model of sepsis-induced acute kidney injury. MATERIALS: Wistar rats were divided into seven groups (seven per group), which were either untreated (control) or treated with LPS, LPS + Ex, LPS + ExOlv, LPS + Olv, LPS + Omg, or LPS + Pal. RESULTS: Lower values of creatinine clearance and blood pressure were observed in the LPS-treated group, and these values were not affected by Ex, Olv, ExOlv, Pal, or Omg treatment. Mortality rates were significantly lower in rats exposed to LPS when they were also treated with Ex, ExOlv, Olv, Pal, or Omg. These treatments also decreased oxidative stress and inflammation (Tumor necrosis factor alpha, interleukin-1 beta) and increased interleukin-10 levels and cell proliferation, which were associated with decreased apoptosis in kidney tissue. CONCLUSION: Ex and Pal treatments were beneficial in septic rats, since they increased survival rate and did not aggravate inflammation. However, the most effective treatments for septic rats were Olv in comparison to Omg. These natural food substances could enable the development of effective therapeutic interventions to sepsis.

Xanthine oxidase inhibitors and sepsis.

Xanthine oxidase activation occurs in sepsis and results in the generation of uric acid (UrAc) and reactive oxygen species (ROS). We aimed to evaluate the effect of xanthine oxidase inhibitors (XOis) in rats stimulated with lipopolysaccharide (LPS). LPS (10 mg/kg) was administered intraperitoneally (i.p.) immediately after allopurinol (Alo, 2 mg/kg) or febuxostat (Feb, 1 mg/kg) every 24 h for 3 days. To increase UrAc levels, oxonic acid (Oxo) was administered by gavage (750 mg/kg per day) for 5 days. Animals were divided into the following 10 groups (n = 6 each): (1) Control, (2) Alo, (3) Feb, (4) LPS, (5) LPSAlo, (6) LPSFeb, (7) Oxo, (8) OxoLPS, (9) OxoLPSAlo, and (10) OxoLPSFeb. Feb with or without Oxo did not aggravate sepsis. LPS administration (with or without Oxo) significantly decreased the creatinine clearance (ClCr) in LPSAlo (60%, P < 0.01) versus LPS (44%, P < 0.05) and LPSFeb (35%, P < 0.05). Furthermore, a significant increase in mortality was observed with LPSAlo (28/34, 82%) compared to LPS treatment alone (10/16, 63%) and LPSFeb (11/17, 65%, P < 0.05). In addition, increased levels of thiobarbituric acid reactive substances (TBARS), tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 were observed at 72 h compared to the groups that received LPS and LPSFeb with or without Oxo. In this study, coadministration of Alo in LPS-induced experimental sepsis aggravated septic shock, leading to mortality, renal function impairment, and high ROS and proinflammatory IL levels. In contrast, administration of Feb did not potentiate sepsis, probably because it did not interfere with other metabolic events.

The effect of hypoxia and reoxygenation in the response of mesangial cells to angiotensin II in vitro / Efeito da hipóxia e reoxigenação na resposta à angiotensina II em células mesangiais in vitro

INTRODUCTION: Mesangial cells (MC) may be involved in the glomerular alterations induced by ischemia/reperfusion injury. OBJECTIVE: To evaluate the response of immortalized MC (IMC) to 30 minutes of hypoxia followed by reoxygenation periods of 30 minutes (H/R30) or 24 hours (H/R24). METHODS: The intracellular calcium concentration ([Ca+2]i) was measured before (baseline) and after adding angiotensin II (AII, 10-5 M) in the presence and absence of glybenclamide (K ATP channel blocker). We estimated the level of intracellular ATP, nitric oxide (NO) and PGE2. RESULTS: ATP concentration decreased after hypoxia and increased after reoxygenation. Hypoxia and H/R induced increases in basal [Ca+2]i. AII induced increases in [Ca+2]i in normoxia (97 ± 9%), hypoxia (72 ± 10%) or HR30 (85 ± 17%) groups, but there was a decrease in the response to AII in group H/R24 since the elevation in [Ca+2]i was significantly lower than in control (61 ± 10%, p < 0.05). Glybenclamide did not modify this response. It was observed a significant increase in NO generation after 24 hours of reoxygenation, but no difference in PGE2 production was observed. Data suggest that H/R injury is characterized by increased basal [Ca+2]i and by an impairment in the response of cells to AII. Results suggest that the relative insensibility to AII may be at least in part mediated by NO but not by prostaglandins or vasodilator K ATP channels. CONCLUSION: H/R caused dysfunction in IMC characterized by increases in basal [Ca+2]i during hypoxia and reduction in the functional response to AII during reoxygenation.

INTRODUÇÃO: Células mesangiais (CM) podem estar envolvidas na lesão glomerular induzida por hipoxia/reperfusão (H/R). OBJETIVO: Avaliar a resposta de CM imortalizadas (CMI) à hipoxia por 30 minutos seguida de reoxigenação por 30 minutos (H/R30) ou 24 horas (H/R24). MÉTODOS: Concentração de cálcio intracelular ([Ca+2]i) foi avaliada antes (basal) e após a adição de angiotensina II (AII, 10-5 M), na presença e na ausência de glibenclamida (bloqueador de canais K ATP). Foram estimados o nível de ATP intracelular, de óxido nítrico (NO) e de PGE2. RESULTADOS: Nível de ATP diminuiu após hipóxia e aumentou após a reoxigenação. H/R induziu aumento na [Ca+2]i basal. A AII elevou a [Ca+2]i nas condições de normoxia (97 ± 9%), hipoxia (72 ± 10%) ou HR30 (85 ± 17%), porém no grupo H/R24, houve diminuição significativa na resposta à AII, uma vez que a elevação da [Ca+2]i foi mais baixa do que no controle (61 ± 10%, p < 0,05). Glibenclamida não alterou esta resposta. Houve um aumento significativo na geração de NO após 24 horas de reoxigenação, mas não foi observada nenhuma diferença na produção de PGE2. Os dados indicam que a injuria celular causada pela hipoxia/reoxigenação é caracterizada pelo aumento na [Ca+2]i basal e por uma diminuição na reatividade celular à AII. Resultados sugerem que a insensibilidade ao agonista constritor pode ser pelo menos em parte, mediada pelo NO, mas não pelas prostaglandinas ou por canais K ATP. CONCLUSÃO: H/R resultou em disfunção das CMI, caracterizada pelo aumento na [Ca+2]i basal durante a hipóxia e redução da resposta funcional a AII durante a reoxigenação.

The effect of hypoxia and reoxygenation in the response of mesangial cells to angiotensin II in vitro.

INTRODUCTION: Mesangial cells (MC) may be involved in the glomerular alterations induced by ischemia/reperfusion injury. OBJECTIVE: To evaluate the response of immortalized MC (IMC) to 30 minutes of hypoxia followed by reoxygenation periods of 30 minutes (H/R30) or 24 hours (H/R24). METHODS: The intracellular calcium concentration ([Ca+2]i) was measured before (baseline) and after adding angiotensin II (AII, 10-5 M) in the presence and absence of glybenclamide (K ATP channel blocker). We estimated the level of intracellular ATP, nitric oxide (NO) and PGE2. RESULTS: ATP concentration decreased after hypoxia and increased after reoxygenation. Hypoxia and H/R induced increases in basal [Ca+2]i. AII induced increases in [Ca+2]i in normoxia (97 ± 9%), hypoxia (72 ± 10%) or HR30 (85 ± 17%) groups, but there was a decrease in the response to AII in group H/R24 since the elevation in [Ca+2]i was significantly lower than in control (61 ± 10%, p < 0.05). Glybenclamide did not modify this response. It was observed a significant increase in NO generation after 24 hours of reoxygenation, but no difference in PGE2 production was observed. Data suggest that H/R injury is characterized by increased basal [Ca+2]i and by an impairment in the response of cells to AII. Results suggest that the relative insensibility to AII may be at least in part mediated by NO but not by prostaglandins or vasodilator K ATP channels. CONCLUSION: H/R caused dysfunction in IMC characterized by increases in basal [Ca+2]i during hypoxia and reduction in the functional response to AII during reoxygenation.

The role of growth factors on renal tubular cells submitted to hypoxia and deprived of glucose.

BACKGROUND: In acute renal failure (ARF) renal tubular cell death and detachment can be induced by necrotic and apoptotic mechanisms. Several studies have demonstrated some benefits of the use of growth factors in experimental models of ARF. METHODS: MDCK cells were cultured in a glucose-free medium for 24h and were submitted to hypoxia (PO2 around 35 mmHg) for additional 24 h. To evaluate the possible protective role of growth factors, EGF, IGF-I or HGF were added to the medium (20 ng mL). LDH release, viability (acridine orange and ethidium bromide dyes) and quantification of apoptotic cells (Hoechst 33342 dye fluorescence) were determined. RESULTS: In the injury group, an increase on LDH release (60% vs. 3%) and on number of apoptotic cells (22% vs. 0.2%) which was associated with a reduced cell viability (61% vs. 94%) when compared with controls. Only HGF, not EGF or IGF-I, was able to protect cells from injury. HGF caused a significant reduction on LDH release (30%) and on number of apoptotic cells (5%), with an increase on viability cellular (79%). CONCLUSIONS: HGF decreases cell death on MDCK cells after hypoxic-induced injury, probably acting in both necrotic and apoptotic mechanisms.