Neuroinflammation, neurodegeneration and alteration of spatial memory in BALB/c mice through ampicillin-induced gut dysbiosis; NOS2 and NFL involvement in a microbiota-gut-brain axis model.

We aimed to investigate ampicillin (AMP) mechanisms in microbiota-gut-brain axis. We evaluated its effect on two gut and brain regions and behavioral performances. We administred AMP (1 g/l) to BALB/c mice for 21 days. Then, we analyzed body weigth change, stool consistency scoring, gut length, intestinal microbiota composition, nitric oxide synthase 2 (NOS2) expression and tissue integrity. We subsequently evaluated NOS2, GFAP, CD68 and NFL cerebral expression and spatial memory.Interestingly, our data showed gut microbiota disruption, NOS2 upregulation and tissue damage, associated to cerebral NOS2, GFAP, CD68 and NFL over-expression and behavioral alteration. Antiobiotic therapy should be prescribed with great caution.

First detection and molecular characterization of rabbit hemorrhagic disease virus (RHDV) in Algeria.

Since the first detection of rabbit hemorrhagic disease (RHD), the rabbit hemorrhagic disease virus (RHDV) has been responsible for high morbidity and mortality worldwide, both in domestic and in wild rabbits. Despite the apparent control of RHD in rabbitries through vaccination, several studies highlighted the rapid evolution of RHDV by recombination, which may facilitate the emergence of new pathogenic strains. The aim of this study was to confirm the presence and characterize RHDV in Algeria. For this, rabbit samples were collected in the north of Algeria, between 2018 and 2021, from small farms where the virus was suspected after the sudden death of a high number of rabbits, and from healthy hunted wild rabbits. The domestic rabbits revealed clinical signs and lesions that were suggestive of RHD. RT-PCR showed that 79.31% of the domestic rabbit samples were positive for RHDV, while in 20.69%, including the hunted rabbits, the virus was not detected. Phylogenetic analysis of the Algerian strains allowed the confirmation and identification as GI.2 (RHDV2), and showed a close relation to GI.3P-GI.2 recombinant strains, suggesting a potential introduction from other countries, with an older strain potentially originated from neighboring Tunisia, while more recent isolates grouped with strains from North America. Our study reports for the first time the presence of GI.2 (RHDV2) in Algeria with multiple routes of introduction. Consequently, we propose that RHDV control in Algeria should be based on epidemiological surveys in association with an adequate prophylactic program.

Molecular characterization of zoonotic Cryptosporidium spp. and Giardia duodenalis pathogens in Algerian sheep.

Little is known about the presence of Cryptosporidium spp. and Giardia duodenalis in Algerian sheep, nor their potential role as zoonotic reservoirs. This study aimed to investigate the occurrence and distribution of these two protists in lambs. A total of 83 fecal samples were collected from lambs (< 40 days old) from 14 different farms. Samples were screened for Cryptosporidium spp. and Giardia duodenalis presence using immunofluorescent techniques (IF). Nested PCR of the small subunit ribosomal RNA (rRNA) gene, followed by restriction fragment length polymorphism (PCR-RFLP) and sequence analyses were used to identify Cryptosporidium species. C. parvum was further subtyped by sequencing the highly polymorphic 60 kDa glycoprotein (gp60) gene. For G. duodenalis, nested PCR of the glutamate dehydrogenase (gdh) and triose phosphate isomerase (tpi) genes was performed and then PCR-RFLP was used to identify G. duodenalis assemblages. Cryptosporidium oocysts and Giardia cysts were detected in 36/83 (43%) and 23/83 (28%) of fecal samples, respectively. Of the 21/36 (58%) Cryptosporidium samples that were positive with IF, 16/21 (76%) were identified as C. parvum, and 5/21 (24%) as C. ubiquitum. From 15C. parvum isolates, 2 subtypes were identified within the IIa subtype family, including IIaA21G2R1 (3/15) and IIaA13G2R1 (1/15), while IIdA16G1 (11/15) was the only subtype identified from the IId subtype family. Of the 16/23 (69%) G. duodenalis IF-positive samples, the most frequent assemblage was ruminant-specific assemblage E (10/16), followed by assemblage D (4/16), and A + E mixed assemblages (2/16). This study is the first to identify and genotype both Cryptosporidium spp. and Giardia duodenalis in Algerian lambs, and is also the first to describe G. duodenalis assemblage D in small ruminants. The presence of zoonotic C. parvum subtype families (IIa, IId), C. ubiquitum, as well as G. duodenalis assemblage A + E, indicates that sheep could play an important role as a potential reservoir for protists.