Oxidative Stress
Effects on Your Dog’s Health and Longevity
Oxidative stress is an issue that affects humans and our dogs alike.
Oxidation is a normal, and necessary, process that takes place in your body. Oxidative stress, however, occurs when there’s an imbalance between free radical activity and antioxidant activity. When functioning properly, free radicals can help fight off pathogens. Pathogens lead to infections.
When there are more free radicals present than can be kept in balance by antioxidants, the free radicals can start doing damage to fatty tissue, DNA, and proteins in your body. Proteins, lipids, and DNA make up a large part of your body, so that damage can lead to a large number of chronic diseases.
Oxidative stress can occur during physiological situations such as growth and intense physical activity. This process is involved in aging but is also linked to the pathogenesis and development of many diseases, including obesity, central nervous system disease, urinary tract disorders, kidney diseases and others.
Antioxidants are substances able to neutralise/stabilise free radicals and protect membrane and cytosolic components against free radical damage. As free radical scavengers these substances represent a major defence against oxidative stress. There are two classes of antioxidants: primary and secondary. Primary antioxidants are endogenous enzymes able to control free radical production. Secondary antioxidant molecules act downstream by neutralizing produced free radicals.
Primary antioxidants are essential antioxidant enzymes naturally produced by our body. These internal antioxidant enzymes serve as our body’s most potent defence against free radicals and harmful inflammatory reactions. There are only 3 primary-antioxidants: Superoxide dismutase (SOD), Catalase (CAT) and Glutathione Peroxidase (GPx). Thanks to their complementary and synergic mechanism of action against free radicals, SOD, CAT and GPx prevent the development of oxidative stress.
Secondary antioxidants are externally provided from dietary sources, such as vitamins (Vitamins C and E), minerals (Se, Cu, Zn, Mn) and carotenoids and flavonoids.
When it comes to dietary supplementation, the optimal antioxidant strategy should combine primary and secondary antioxidant molecules to target several steps in the oxidative pathway and to obtain a synergistic effect.
Antioxidant Phytochemicals:
Phytochemicals are the antioxidants that are naturally used by plants to protect themselves against free radicals. Studies show that dogs (and their owners!) who eat sources of phytochemicals also benefit from the antioxidant properties of the plant through a regulation of highly damaging oxidative stress and overall improvement of physical and mental health. (1, 2, 3, 4, 5, 6, 7, 8, 9) Phytochemicals are broken down into the following categories:
• Carotenoids
• Flavonoids
• Allyl Sulphides
• Polyphenols
Carotenoids:
Carotenoids, including beta-carotene, alpha-carotene and lycopene, are vitamin A precursors that act as antioxidants and may counteract oxidative damage to the body, which plays a role in the development of chronic diseases such as heart disease, diabetes and cancer.
Beta-carotene has received attention for its possible role in the prevention of several chronic diseases, including cancer and cardiovascular disease.
Although alpha-carotene is chemically similar to beta-carotene, studies have suggested that alpha-carotene is around ten times more effective than beta-carotene in inhibiting the development of cancer cells, and that it has more potent results in reducing the effects of liver cancer and inhibiting the tumour-promoting actions of glycerol in lung carcinogenesis and skin tumours. (1)
β-carotene – β-carotene is the most potent carotenoid precursor to vitamin A. Vitamin A is essential for biochemical and physiological processes in the body including vision, reproduction, cellular differentiation, gene expression, immunity and growth. Carotenoids are pigments in plants that are usually yellow or red. Antioxidants such as beta carotene play crucial roles in the body’s fight against free radicals. There’s a lot of evidence to support the intake of antioxidants to help reach optimal wellness.
Foods Rich in Beta-Carotene include:
α-Carotene – like beta carotene, alpha carotene is found in a variety of vegetables and fruits and is a precursor to Vitamin A. Cleavage of alpha carotene in the body produces retinol and alpha retinol whereas cleavage of beta carotene produces two retinol molecules.
α-Carotene has been shown in large numbers of studies to offer significant health benefits including decreasing risks of mortality from cardiovascular disease, cancer, and other causes. (1)
Other benefits include improved colon, heart, bone and eye health (2, 3, 4, 5)
Foods Rich in Alpha-Carotene include:
- Pumpkin
- Carrots
- Sweet potatoes
Lycopene – is a nutrient in the carotenoid that’s naturally found in some plants. Lycopene provides the pigment that gives red and pink fruits like tomatoes, red carrots, watermelons and papayas their colour and is known to have powerful antioxidant properties.
Clinical trials have shown that lycopene benefits include reducing the risk of cardiovascular disease, lowering cholesterol, blood pressure, inflammation, and oxidative stress, including free radical damage to LDL cholesterol. (1, 2, 3, 4, 5, 6)
Foods Rich in Lycopene include:
- Tomatoes
- Guava
- Watermelon
- Rose hips
- Papaya
- Basil
Beta-Cryptoxanthin – belongs to the class of carotenoids, more specifically the xanthophylls. In the human body, beta-cryptoxanthin is converted to vitamin A (retinol) and is considered as a pro-vitamin A.
Beta-cryptoxanthin is a strong antioxidant and prevents the free radical’s damage to the body’s cells and DNA. Studies have shown it to reduce the risk of lung cancer and colon cancer as well as reducing the risk of rheumatoid arthritis and age-related macular degeneration. (1, 2, 3, 4, 5, 6, 7, 8)
Food Rich in Beta-Cryptoxanthin include:
- Pumpkin
- Papaya
- Rosehips
- Carrots
- Peppers
Flavones – Natural flavones, as well as some of their synthetic derivatives, have been shown to exhibit several biological activities, including antioxidant, anti-inflammatory, antitumor, anti-allergic, neuroprotective, cardioprotective and antimicrobial. The antioxidant properties of flavones allow them to demonstrate potential application as preventive and attenuating agents in oxidative stress, i.e., a biological condition that is closely associated to aging processes and to several diseases. (9)
Rich Sources of Apigenin (Flavones):
Although it is found in many fruits, vegetables and herbs, the amount of it varies. The richest natural sources are:
- Parsley
- Celery
- Spices such as rosemary, oregano, thyme, basil and coriander
- Chamomile
- Cloves
- Lemon Balm
- Artichokes and Spinach
- Peppermint
- Liquorice
Rich Sources of Luteolin (Flavones) http://phenol-explorer.eu/contents/polyphenol/229
- Chamomile
- Olive Oil
- Sage
- Oregano
- Rosemary
Isoflavones – Isoflavones are a class of flavonoids that exhibit antioxidant, anticancer, antimicrobial, and anti-inflammatory properties. Increasing evidence has highlighted the potential for isoflavones to prevent the chronic diseases in which inflammation plays a key role. (10)
Foods Rich in Isoflavones:
- Chickpeas
- Fava Beans
- Peas
Flavanols – represent a specific group of bioactives, or plant-derived nutrients, within the larger family of natural compounds known as flavonoids. Published research has shown regular consumption of dietary flavanols can promote healthy blood vessel function and slow oxidative damage. (11)
Rich sources of Flavanols include:
- Cranberries
- Spinach
- Kale
- Parsley
Flavanones – Flavanones are associated with a number of health benefits because of their free radical-scavenging properties. They are linked to cardiovascular health, relaxation and general antioxidant as well as anti-inflammatory activity.
Sources of Flavanones include:
- Ginger
- Lemons
- Limes
The human body does not produce antioxidant vitamins naturally, so it is essential to include dietary sources of them in our daily intake of food, be it through foods or supplements. Common antioxidant vitamins include vitamins A, C, E, folic acid, and beta-carotene.
Vitamin A is an essential vitamin for dogs, which means it must be part of their diet in order for your dog to maintain optimal health. Skin, coat, muscles and nerves all require vitamin A for proper function. If a dog does not get enough Vitamin A in their diet, you will first notice that their skin and coat do not look healthy or they may suffer from night blindness. Muscles will deteriorate and your dog will feel weak. Vitamin A is especially important for pregnant females and puppies because growing puppies require it for growth, muscle and neurological development.
Rich Sources of Vitamin A – http://www.whfoods.com/genpage.php?tname=nutrient&dbid=106
- Sweet Potato
- Carrots
- Spinach
- Kale
- Parsley
Vitamin E is more than good for dogs – it’s essential! Vitamin E is an antioxidant that can help defend the body against free radicals in the skin and other cells. Vitamin E is also an essential, fat-soluble vitamin that is good for a dog’s immune system, muscles, heart health, liver, nerve cell membranes and healthy skin and coat. Vitamin E is also regarded for its anti-inflammatory benefits.
Foods rich in Vitamin E:
- Spinach
- Sweet Potato
Antioxidant Enzymes – Catalase, Glutathione Peroxidase and Superoxide Dismutase (SOD)
Reactive oxygen species (ROS) is a term that encompasses all highly reactive, oxygen containing molecules, including free radicals.
Types of ROS include the hydroxyl radical, the superoxide anion radical, hydrogen peroxide, singlet oxygen, nitric oxide radical, hypochlorite radical, and various lipid peroxides. All are capable of reacting with membrane lipids, nucleic acids, proteins and enzymes, and other small molecules, resulting in cellular damage.
Antioxidant enzymes are proteins involved in the catalytic transformation of reactive oxygen species and their by-products into stable nontoxic molecules therefore representing the most important defence mechanism against oxidative stress-induced cell damage.
The following table outlines various Reactive oxygen species (ROS) and their neutralising antioxidants.
| ROS | NEUTRALIZING ANTIOXIDANTS |
| Hydroxyl radical | Vitamin C, Glutathione Flavonoids, Lipoic acid |
| Superoxide radical | Vitamin C, Glutathione, Flavonoids, SOD |
| Hydrogen peroxide | Vitamin C, Glutathione, beta carotene, Vitamin-E, flavonoids, lipoic acid, catalase |
| Lipid peroxides | Beta-carotene, Vitamin-E, Ubiquinone, flavonoids, Glutathione peroxidase |
Plant-Based Foods rich in Catalase:
- Sweet Potato
- Carrot
- Kale
- Spinach
- Pineapple
Plant-Based Foods rich in Glutathione Peroxidase:
- Spinach
Food rich in Superoxide Dismutase:
- Kale
- Turmeric
- Sage
- Rosemary
Canine Nutritionist and vet formulated to include a wide variety of ingredients providing a blend of primary and secondary antioxidants, Bonza’s 100% plant-based dog food offers excellent support against oxidative stress for your dog.
Nose to Tail Good Health.
