Can diabetes mellitus modify the plasma concentrations of rifampicin in patients under treatment for tuberculosis?

Abstract Rifampicin is a key component of treatment for tuberculosis and its efficacy is determined by the blood levels attained after therapeutic doses. However, there is a high variability of rifampicin blood levels that is related to both the patient and the formulation used. To date, the effect of diabetes mellitus on the plasma levels of rifampicin was low exploited, which could be relevant either by the significant increase of the comorbidity worldwide as by the probable influence of diabetes on the rifampicin exposure. The study aims to evaluate whether diabetes mellitus contribute to the variation of the maximum concentration of rifampicin in patients with tuberculosis treated with a daily dose of 10 mg/kg. Rifampicin and glycated hemoglobin were measured by high-performance liquid chromatography, and blood glucose by spectrophotometry. A total of 62 male patients were included in the study, and 26 presented diabetes mellitus. Rifampicin plasma levels in 2-h plasma samples collected at day 61 ranged from 3 µg/mL to 14.2 µg/mL. Drugs levels were similar between diabetic and non-diabetic patients and were not correlated with blood glucose and glycated hemoglobin. Moreover, a high percentage of patients in both groups presented low levels of rifampicin.

Can diabetes mellitus modify the plasma concentrations of rifampicin in patients under treatment for tuberculosis?

Rifampicin is a key component of treatment for tuberculosis and its efficacy is determined by the blood levels attained after therapeutic doses. However, there is a high variability of rifampicin blood levels that is related to both the patient and the formulation used. To date, the effect of diabetes mellitus on the plasma levels of rifampicin was low exploited, which could be relevant either by the significant increase of the comorbidity worldwide as by the probable influence of diabetes on the rifampicin exposure. The study aims to evaluate whether diabetes mellitus contribute to the variation of the maximum concentration of rifampicin in patients with tuberculosis treated with a daily dose of 10mg/kg. Rifampicin and glycated hemoglobin were measured by high-performance liquid chromatography, and blood glucose by spectrophotometry. A total of 62 male patients were included in the study, and 26 presented diabetes mellitus. Rifampicin plasma levels in 2-h plasma samples collected at day 61 ranged from 3µg/mL to 14.2µg/mL. Drugs levels were similar between diabetic and non-diabetic patients and were not correlated with blood glucose and glycated hemoglobin. Moreover, a high percentage of patients in both groups presented low levels of rifampicin.

Levels of primaquine and carboxyprimaquine in patients with malaria vivax from the Brazilian Amazon basin.

In the last two years, a substantial increase in the number of malaria vivax cases has occurred in the Brazilian Amazon basin. The adequate exposure of hypnozoites to primaquine is a matter of interest as these dormant forms are responsible for the maintenance or even the increase of malaria burden in endemic areas. The aim of this study was to estimate the levels of primaquine and carboxyprimaquine in whole blood samples of patients with P. vivax treated with chloroquine and an abbreviated regimen of primaquine (0.5 mg/kg/d for 7 days), with adequate clinical and parasitological outcomes after 180 days of follow-up. A total of 40 male patients met the criteria for inclusion in the study. Primaquine and carboxyprimaquine were measured by high-performance liquid chromatography. The levels of primaquine in whole blood samples ranged from 40-238 ng/mL, 42-196 ng/mL and 42-150 ng/mL on days 1, 3 and 7. The levels of carboxyprimaquine in whole blood samples ranged from 87-234 ng/mL, 96-252 ng/mL and 74-448 ng/mL on days 1, 3 and 7. These data provide a reliable estimation of exposure of the infecting parasite to primaquine. Based on the regional pattern of relapse, the estimated blood levels of primaquine can be considered effective against hypnozoites of the local circulating strains of P. vivax.

Petiveria alliacea exerts mnemonic and learning effects on rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Petiveria alliacea L. (Phytolaccaceae) is a perennial shrub native to the Amazon region and other tropical areas such as Central America and the Caribbean. Popularly known as mucuracaá, P. alliacea is used in the folk medicine for a broad variety of therapeutic purpose and also in religious ceremonies by slaves as a sedative, which highlights its properties on the Central Nervous System (CNS). AIM OF THE STUDY: The present study evaluated the effects of the P. alliacea leaves hydroalcoholic extract (PaLHE) on the cognition, including learning and memory. MATERIAL AND METHODS: Three-month-old male and female Wistar rats (n=8-10/group) were administered with 900mg/kg of PaLHE. The behavioral assays included Step-down Inhibitory avoidance (IA) and Morris Water Maze (MWM) tests. RESULTS: Consistent with our previous reports, P. alliacea improved long-term memory. It also exerted previously unreported effects on short-term and spatial memory improvement, and increased learning in the tasks. CONCLUSIONS: The P. alliacea extract elicited mnemonic effects and improved the learning process in both IA and MWM tests. Our results highlight the importance of further studies in order to identify the active substances of the PaLHE and investigate the pharmacological mechanisms that underlies the reported effects.