Dr Lisa Landymore-Lim, a British chemist specializing in immunology and biomedical chemistry, became curious about the explosion of childhood illnesses such as asthma and diabetes, and carried out a pilot study of drug-prescribing among juvenile diabetics. In 1994, WDDTY published her initial findings. Here is her evidence for suggesting a link between the excessive use of antibiotics and diabetes.
Cases of chemicals and drugs causing temporary and permanent insulin-dependent diabetes (IDD) are well documented in the medical literature (Pharmacol Rev, 1970; 2: 485-518; J Rheumatol, 1987; 14: 732-5). Unfortunately, such cases don't usually come to the attention of physicians, and most patients are completely unaware of these potential hazards.
Two of the best-known chemicals capable of damaging pancreatic beta cells-responsible for the production of insulin-are the antibiotic streptozocin (Zanosar®, also used in chemotherapy) and the chemical alloxan. These drugs are routinely used in animal experiments to study diabetes. Vacor, a rat poison, has also been reported to cause the disease.
There is a structural similarity between the chemicals streptozocin, alloxan and Vacor: in each, there is at least one oxygen atom joined by two bonds to a carbon atom (C=O), forming a carbonyl group, which is flanked on each side by a nitrogen (N) atom.
This is of interest because carbonyl groups and nitrogen atoms can be considered reactive species due to their excess of negative charge. This means that they are electron-rich and, thus, have an affinity for positively charged species such as zinc ions (Zn2+). Thus, they behave like magnets, attracting oppositely charged species.
Insulin is stored in the pancreas together with zinc. In fact, the pancreas has the highest concentration of zinc in the body, making it potentially a major target for chemical attack.
In addition, double-bonded oxygen groups are also potential sources for the formation of free radicals, those destructive agents that have been implicated in the onset of cancer.
Other chemicals known to be capable of producing diabetes in humans include the drugs dapsone, used in the treatment of leprosy, and pentamidine isethionate, an anti-protozoal agent used to treat pneumonia in AIDS patients.
However, dapsone and pentamidine bear little structural resemblance to streptozocin and alloxan, except that dapsone does contain electronegatively charged oxygen atoms that are double-bonded to sulphur (instead of carbon). Both drugs also have electronegative terminal amino (NH2) groups attached to, or in close proximity of, a benzene ring.
Nevertheless, comparison of daps-one and pentamidine with the drugs frusemide and chlorthiazide, diuretics reportedly associated with the onset of diabetes, also reveals structural similarities. In frusemide, once again we see the electronegative sulphonyl (S=O) group and a terminal amino (NH2) group, whereas chlorthiazide has two SO2 groups and a terminal NH2.
Such groups are not commonly found in drugs. In the American Hospital Formulary Service Drug Information database, which lists some 1000 drugs, less than 5 per cent have either an amino group or a carbon atom bound to a benzene ring.
Sulphonyl groups, however, are commonly found in thiazide diuretics and sulphonamide drugs. Alarmingly, in Australia, diuretics like hydrochlorthiazide (identical to chlorthiazide except for an additional hydrogen atom) are given to young women to treat premenstrual water retention.