Author: Kari Kenefick

Catnip and Its Effect on Cats, Dogs and Humans

Posted on by Kari Kenefick
Feline in catnip.
Common cat behavior around catnip.

Cat owners—and those that care about cats—know the power that catnip has on cats. If you own a cat and bring catnip into the house, no matter where you put it, the cat will find it.

Once the cat gets the catnip (aka catmint, nepeta) she/he will rub her/his head and shoulders on the plant,  lie down on it or even dash about the house. Cats frequently chew on and eat catnip.

A report sought to explain why and how catmint affects cats. I eagerly read the report, having always been conflicted about giving catnip to my cats. Could they be killing brain cells by smelling or consuming catnip? Is it habit forming? Is catnip a gateway drug for cats? Continue reading “Catnip and Its Effect on Cats, Dogs and Humans”

The Benefit of a Cold, Dark Walk: Fall Waterfowl Migration in the Central United States

Posted on by Kari Kenefick

Migrating geeseDriving to work in the morning the past several weeks, there have been occasional large flocks of geese and ducks flying . In the northern U.S. it’s time for the fall waterfowl migration south. In fact, the flock sizes have decreased in the past week, and several online sources concur that waterfowl migration has peaked,  in mid December. Continue reading “The Benefit of a Cold, Dark Walk: Fall Waterfowl Migration in the Central United States”

A New Role for Reactive Oxygen Species: Can We be Aged and Thin?

Posted on by Kari Kenefick
Add pomegranite to the list of so-called superfoods.

Since the 1980s, we’ve been told that aging can be accelerated by a build-up of free radicals in our cells. We’ve learned that to counteract the damage that free radicals (or reactive oxygen species, ROS) can wreak on our bodies, we should consume  antioxidants like vitamins C and E, and phytochemicals.

In fact, the term “superfood” was coined for foods that contain high levels of antioxidants, phytochemicals and vitamins, foods like blueberries and carrots, spinach and kale, to name a few.

 “Hold the phone”, as a pre-calculus professor of mine used to say.  Turn off the blender and put down that shot glass of beet-carrot-lemon grass juice. This research just in: “Free Radicals Crucial to Suppressing Appetite”.

The research was published August 28, 2011 in the advanced online edition of Nature Medicine.

In this study, Yale University researchers reported that elevated levels of ROS  in the brain activated satiety-generating neurons. Continue reading “A New Role for Reactive Oxygen Species: Can We be Aged and Thin?”

This is Your Hippocampus on Cortisol

Posted on by Kari Kenefick
A maze photo.
Whether navigating a maze or other obstacles, decreasing stress will help.

Research published by  Dr. Joyce Yau et al. in the Journal of Neuroscience earlier this year examined whether negative effects of cortisol on memory could be blocked using antagonists for brain receptors for cortisol.

The researchers noted that  local brain amplification of glucocorticoids (cortisol)  by 11beta-hydroxysteriod dehydrogenase type 1 (11beta-HSD1) is “pivotal” in age-related memory loss.

Cortisol acts by binding to cell receptors. In their research, Yau and colleagues found that when levels of cortisol are low, a particular cortisol receptor is bound. However, at higher concentrations, cortisol has a spillover effect and binds a second receptor. Binding to this second receptor activates cellular processes in the brain that cause memory impairment.

The  receptors studied were the high-affinity mineralocorticoid receptor (MR) and low-affinity glucocorticoid receptor (GR). As models for memory impairment, they used aged C57BL/6J mice as controls. Also studied were 11beta-HSD1-deficient mice (-/-), which ordinarily show no age-related memory deficits. Mouse memory was tested with a spatial memory task, a Y maze.

Continue reading “This is Your Hippocampus on Cortisol”