An Investigation into the Immunomodulatory Activities of Sutherlandia frutescens in Healthy Mice.

Sutherlandia frutescens is a medicinal plant that has been traditionally used in southern Africa for cancers, infections, and inflammatory conditions. We recently published experiments demonstrating that an aqueous extract of S. frutescens possessed potent immune-stimulatory activity. This work was carried out with murine macrophages, an immune cell type that plays a pivotal role in host defense from infection and in shaping host inflammatory and immune responses. Here, we conducted a series of follow-up experiments to explore the impact of consuming S. frutescens on host response to bacterial challenge using healthy mice. We found that feeding mice a diet containing S. frutescens failed to significantly alter host response to systemic infection by either a gram-positive or gram-negative bacterium (i.e., L. monocytogenes and E. coli, respectively). In contrast to the in vitro observations, we found no evidence that S. frutescens consumption stimulated in vivo inflammatory responses; instead, consumption of S. frutescens tended to diminish in vivo inflammatory responses. Several possible reasons for this are discussed.

Effect of soy and milk protein-related compounds on Listeria monocytogenes infection in human enterocyte Caco-2 cells and A/J mice.

Listeria monocytogenes causes listeriosis in humans, mainly through the consumption of ready-to-eat foods such as cheese. Immunocompromised persons, the elderly, and pregnant women and their fetuses or newborns are at the highest risk for the infection. We examined the effects of dietary milk-casein (MC) and soy-protein (SP), and their digested compounds tryptone (TP) and phytone peptone (PP), respectively, on L. monocytogenes invasion and infection in human enterocyte-like Caco-2 cells and A/J mice. Invasion into Caco-2 cells tended to be high with TP. In A/J mice orally infected with L. monocytogenes, viable numbers in the liver and spleen showed a tendency of decreasing with the 20% SP diet compared to the 20% MC diet. SP suppressed the inflammation marker tumour necrosis factor-α in spleen tissue. Furthermore, bacteria lipopolysaccharide (LPS)-stimulated nitric oxide (NO) secretion from murine macrophage RAW 264.7 cells was suppressed by PP more than TP. These results suggest that major dietary proteins might affect infection and inflammation by L. monocytogenes.

Certain dietary carbohydrates promote Listeria infection in a guinea pig model, while others prevent it.

It has been proposed that dietary non-digestible carbohydrates can improve host resistance to intestinal infections by stimulating health-promoting bacteria in the gut. However, evidence from in vivo infection studies is scarce, particularly for gram-positive infections. We studied the effect of five non-digestible carbohydrates on the resistance of guinea pigs to Listeria monocytogenes infections. Animals were fed a diet supplemented with 10% xylooligosaccharides (XOS), galactooligosaccharides (GOS), inulin, apple pectin or polydextrose for three weeks before oral infection with a mixture of three different fluorescently labeled L. monocytogenes strains. Colonisation of L. monocytogenes in the intestine was determined by quantification of L. monocytogenes in faecal, ileal and caecal samples while translocation was determined by quantification of L. monocytogenes in mesenteric lymph nodes, spleen and liver. XOS and GOS significantly (P<0.05) improved the resistance of guinea pigs to L. monocytogenes, while inulin and apple pectin decreased the resistance (P<0.05). No significant effect on resistance to L. monocytogenes was seen after feeding with polydextrose. No difference in caecal weight or pH between the dietary groups was measured, except for a higher caecal weight and a lower caecal pH of animals fed with XOS, and a lower caecal pH for animals fed with polydextrose. In conclusion, this study shows for the first time that different non-digestible carbohydrates can have entirely different effects on the intestinal colonisation and translocation of a pathogenic bacterium.

[Pregnancy in HIV infected women. Current therapeutic indications]. / Grossesse chez la femme infectée par le VIH. Indications thérapeutiques actuelles.

This paper deals with the management of pregnant women with HIV infection. The virus is transmitted by the mother to 20-30 percent of the infants, and therapeutic abortion should be offered to women whose pregnancy does not exceed 26 weeks of amenorrhoea. If pregnancy is pursued, the mother must be investigated for sexually transmitted diseases which are particularly frequent in this population and may have repercussions on the newborn. Pneumocystis carinii pneumonia is the most common opportunistic infection in pregnancy. In case of T4-cell depletion chemotherapy with pentamidine must be instituted. Hygienic and dietetic measures should be applied to avoid listeriosis and toxoplasmosis. Serological tests for toxoplasmosis are necessary in all HIV patients, with chemoprophylaxis in case of increased IgG levels. Thrombocytopenia usually responds to human immunoglobulins. At delivery, there is no need to modify the usual obstetrical procedures. During the post-partum period, another pregnancy must be avoided by good compliance with a reliable contraceptive method. As for the preventive treatment of mother-to-child HIV transmission, at the moment only AZT can be considered, but its effectiveness remains to be evaluated in therapeutic trials.