11/28: Buffington et al. and Reber et al.

The MHFD offspring have many qualities of ASD, it shouldn’t be thought of as a complete model of ASD. Although obese mothers are 1.5 times more likely to have an autistic child, not all children of obese mothers are autistic. Furthermore, not all of these children have dysbiosis of gut microbiota. So, this is model is relevant for some cases of ASD, but not all. Also, only the social deficits are rescued through restoring gut microbiota. A different treatment would be required to rescue the repetitive behaviors and anxiety associated with ASD.

Since L. reuteri administration to MHFD offspring can rescue the social deficits in the reciprocal social interaction test and the three chamber test, I was wondering if administering the bacteria to the HFD mothers would change the gut microbiota of the offspring. Since no negative effects were seen when MRD offspring were given L. reuteri, it doesn’t seem like there would be any negative effects for the mothers. It would be interesting to do an experiment comparing the social behaviors and oxytocin levels of offspring of RD mothers, HFD mothers, and HFD mothers that had been administered L. reuteri.

Reber et al. found that there was a decrease in reactive coping measures and anxiety when mice were administered their final m. vaccae immunization one week prior to the beginning of CSC housing. They found similar results when the interval between immunization and the start of CSC housing was two weeks. To see if the results are even more long-lasting, I think that a longer interval of time between immunization and CSC housing would be more convincing. In the introduction, they claim that the effects can last up to 12 weeks after administration, so I was confused about why they only extended the interval by one week for the second test.

When the stress coping behaviors were assessed on day 15, it seemed like the effects of m. vaccae seemed to be wearing off. The dominance status and submissive behavior scores were the same for vehicle and m. vaccae treated CSC mice. This made me think that the effects of the m. vaccae bacteria were not strong enough to rescue mice from the stress they were going through, since the results were similar for the one week and two week injection to CSC interval.

However, these results have good translational value for patients that suffer from colitis and stress-related disorders. M. vaccae administration prevented colitis in stressful situations. It would be viable to administer m. vaccae to a human patient suffering from these symptoms, and there have been other human studies in the past that have had promising results in immunoregulation studies.